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Items by Reef Maniac

Marine Aquariums of South Africa

• 

  Attention all Bloemfontein reefers - your thoughts please

  Posted: February 19th, 2012, 5:09pm CST by Reef Maniac

  Hi everyone,
  
  Please check this thread Mini-MACSA, anyone??? - Page 4 - Marine Aquariums of South Africa and let's have your thoughts - who would be willing to participate,. and perhaps host some reefers for a weekend in March 2012?
  
  Hennie
• 

  Using a fire extinguisher as a CO2 source for a calcium reactor

  Posted: August 20th, 2011, 11:56pm CDT by Reef Maniac

  There has been quite a lot of talk/questions regarding sources of CO2 gas and cylinders for use with calcium reactors, so I thought that I should show how I DIY'd mine :biggrin:
  
  The CO2 gas used to refill CO2 fire extinguishers is quite pure, even though it is "industrial" quality, and I have been using this gas for many years now without any problems. I previously used an aluminium cylinder from Azoo, which I bough many years ago, but it recently popped it's emergency relief valve, and I just could not find a suitable replacement - so I changed to a larger fire extinguisher cylinder. These cylinders, being made from steel, are much stronger and thus safer than the aluminium cylinders, and much easier to have refilled, as they are all stamped with the SABS mark.
  
  The Azoo regulator and needle valve were pretty bad quality, and did not last more than a few months. I replaced them with a welding regulator (Argon/CO2 type, used for TIG/MIG welding, and bought from our local welding supplier) and an old Whitey needle valve scrounged off a disused laboratory apparatus (they can be bought commercially from Afrox, I think).
  
  So, here's some photos: Note that the cylinder is mounted upside down. This is rather important, as an unmodified extinguisher-type cylinder has a pipe on the inside going down to the bottom of the cylinder, so as to allow liquid CO2 to be ejected onto the fire that one would normally use this for. It is not a good idea, though, to allow liquid CO2 to flow through the regulator, and turning the cylinder upside-down alleviates this problem. I also chose to mount it on a wooden "stand", to make it portable - I can now move it out of my cabinet (it normally stands next to the sump) if I need space to work around the sump.
  
  
  
  The biggest disadvantage of a fire fighting CO2 cylinder is the lack of a shut-off valve, with these cylinders only having a "trigger" type of valve. To overcome this problem, I merely drilled a small hole in the "trigger" bar, and tied the trigger "open" with a short length of copper wire, as can be seen in this next photo:
  
  
  
  Well, there you go - pretty cheap, and it works great :thumbup:
  
  Hennie
• 

  Interesting article regarding marine toxins

  Posted: August 4th, 2011, 9:07pm CDT by Reef Maniac

  Here's an extract from an article regarding paleotoxins and other marine toxins relevant to our hobby. What is really mind boggling is the toxicity of this toxin - 6 grams of a particular paleotoxin can kill 1 BILLION mice, or about 250 000 people (assuming one mouse weighs 20 grams, and one person weight 80kg) :eek:
  
  So please, don't upset your zoanthids :whistling:
  Quote:

  Abstract Zoanthids (Anthozoa, Hexacorallia) are colonial anemones that contain one of the deadliest toxins ever discovered, palytoxin (LD50 in mice 300 ng/kg), but it is generally believed that highly toxic species are not sold in the home aquarium trade. We previously showed that an unintentionally introduced zoanthid in a home aquarium contained high concentrations of palytoxin and was likely responsible for a severe respiratory reaction when an individual attempted to eliminate the contaminant colonies using boiling water. To assess the availability and potential exposure of palytoxin to marine aquarium hobbyists, we analyzed zoanthid samples collected from local aquarium stores for palytoxin using liquid chromatography and high resolution mass spectrometry and attempted to identify the specimens through genetic analysis of 16S and cytochrome c oxidase 1 (COI) markers. We found four specimens of the same apparent species of zoanthid, that we described previously to be responsible for a severe respiratory reaction in a home aquarium, to be available in three aquarium stores in the Washington D.C. area. We found all of these specimens (n = 4) to be highly toxic with palytoxin or palytoxin-like compounds (range 0.5–3.5 mg crude toxin/g zoanthid). One of the most potent non-protein compounds ever discovered is present in dangerous quantities in a select species of zoanthid commonly sold in the home aquarium trade. Introduction In the late 1950's, Dr. Albert H. (Hank) Banner began a program at the University of Hawaii to search for the elusive cause of ciguatera fish poisoning. Dr. Philip Helfrich, a young researcher hired by Banner, began this search by investigating an entry in the Hawaiian dictionary for the “limu-make-o-Hana” (rough translation deadly seaweed of Hana). This legend dates back to Hawaiian antiquity with tales of Shark Gods, sacred pools, and a seaweed when applied to a warrior's spear would “bring sure death” to their enemies. The pool became “kapu” or taboo to the local Hawaiians and it was said that an ill fate would befall anyone who disturbed the sacred site. Every legend holds some basis in fact, and in 1961, Helfrich, accompanied by graduate student John Shupe, tracked down the fabled pool near the village of Mu′olea on the island of Maui and introduced to the world a new species of cnidarian zoanthid (colonial anemone) known as Palythoa toxica. This research led to the discovery of palytoxin (PLTX), one of the most potent natural products ever discovered. Although much of the structural elucidation of palytoxin would be determined from less toxic, but far more abundant, species such as Palythoa tuberculosa none were ever found to be as potent as the samples collected from the tidepools at Mu′olea. Now the legendary limu appears to be exacting its ancient curse once again, but this time upon unsuspecting marine home aquarists. In 2007, we assisted the Georgia poison center in an investigation into a potential dermal intoxication with palytoxin from zoanthids in a home aquarium. During the course of the investigation, we learned of another marine aquarium hobbyist in Virginia who had recently experienced a severe respiratory reaction while trying to eradicate brown non-descript colonies of zoanthids that had arrived as hitchhikers with live rock and were overgrowing more desirable organisms in the tank [account can be found at: http://www.reefcentral.com/forums/showth​read.php?t=1083843 – accessed 12/09/10]. A sample (here called Virginia zoanthid or VAZOA) was found to contain high levels of palytoxin (600 µg crude toxin/g wet zoanthid). Zoanthids are a notoriously problematic taxonomic group and it proved difficult at the time to identify to the species level the sample from the home aquarium in Virginia. Histologic evaluation of preserved polyps could only confirm that it was a Palythoa sp. (D. Fautin, University of Kansas, personal communication). In an attempt to determine the prevalence of palytoxin in aquarium store zoanthids, we purchased several colonies from local aquarium stores and analyzed them for palytoxin. We further performed a molecular analysis in an attempt to identify the colonies to the species level. Conclusions Some of the deadliest toxins known to man come from the sea. Maitotoxin produced by tropical single celled dinoflagellates of the genus Gambierdiscus has an intraperitoneal (IP) lethality (in mice) of 50 ng/kg. Meaning 1 gram of toxin can kill 1 billion mice. It is the most potent non-peptide natural product ever discovered. Palytoxin comes in second with an IP mouse lethality of 300 ng/kg. Even though our typical sample size for zoanthids collected in this study was small (0.2–0.8 g/sample), we calculate that we extracted enough crude toxin from these combined samples to kill 300,000 mice (approx. 2 mg crude toxin calculated by HPLC, standard mouse size of 20 g). Palytoxins, along with several structurally related compounds (e.g. ostreocins and ovatoxins produced by select marine dinoflagellates) have garnered significant recent attention due to the fact that they are one of the few marine toxins that pose a risk to humans through ingestion (consumption of contaminated seafood), inhalation (exposure to palytoxin containing aerosols), and dermal (exposure to select marine zoanthids) routes of exposure. Numerous poisonous and venomous animals are available at your local pet store. Animals imported for the pet/aquarium trade are regulated based on their CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora) status and not based on potential toxicity. Venomous lionfish (family Scorpaenidae), and alkaloid containing poison dart frogs (family Dentrobatidae) are commonplace. Although more rare, highly venomous (with tetrodotoxin) blue ringed octopuses (Hapalochlaena spp.) can occasionally be found in home aquaria. Furthermore, importation of whole tetrodotoxin containing puffer fish (family Tetraodontidae), which are prohibited for importation (whole) as food, have no such restrictions if they are imported as pets. There is great debate among marine aquarium enthusiasts on the hazards of keeping zoanthids. Some literature warns that all zoanthids are toxic, while many hobbyists claim that they have been handling these organisms for years without incident (on-line accounts can be found at sites such as www.reefcentral.com). Well documented cases of human poisonings due to exposure to zoanthids in home aquaria are limited, but detailed exposure accounts with confirmation of toxin presence do exist for inhalational and dermal exposures. Additional case reports based on symptoms alone can also be found in the literature. This is the first report to our knowledge that documents both high PLTX presence and phylogenetic identity for commercially available zoanthids from aquarium stores. It is often difficult to determine the species, let alone geographic origin, for many of the organisms sold in the home aquarium trade. In the case of zoanthids, most specimens are sold under common names such as “button polyps”, “sun polyps”, or “yellow/orange or green zoas”; furthermore, many enthusiasts and websites selling zoanthids use colloquial names such as “watermelon”, “scorpion”, “people eaters”, “sunset” palys or zoas, etc. Discussions with the owner of aquarium store #1 revealed that he typically acquired zoanthids though the purchase of mixed containers of “frags” (i.e. coral or rock fragments containing zoanthid colonies) from either importers or wholesalers who typically reported them to be wild caught and of Indo-Pacific origin but with no other accompanying documentation confirming the geographic origin or identity of the specimens. Making the issue of tracing the origin of commercial zoanthids more difficult is the fact that many marine aquarium enthusiasts commonly fragment their colonies and further exchange them outside of retail sale. All of this uncertainty makes it difficult to provide a concise message to aquarium hobbyists on the hazards of keeping this group of organisms. During this investigation, we found that many of the zoanthids commonly sold in the home aquarium trade are non-toxic or weakly-toxic, but a highly toxic variety of Palythoa (possibly P. heliodiscus or P. toxica) is indeed available. It often occurs as a tank contaminant and can be unintentionally introduced with more desirable species or on live rock. Unfortunately, due to the unavailability of molecular data for P. toxica (the limu make o Hana from Hawaiian folklore), we could not determine its relationship to either the toxic specimens from our study or to P. heliodiscus, which available molecular data suggests our toxic specimens are. Hopefully, one day the type location on the island of Maui will be made available for sampling again and the true identity of P. toxica can be determined. Regardless, we have shown that a Palythoa sp. just as toxic as the legendary limu can not only be found outside of the tidepools at Mu′olea, it is available in retail commerce and present in home aquaria, with the owners often unaware of the deadly poisons they are being exposed to.

  Hennie
• 

  Can NASA please check my tank's salinity...

  Posted: June 10th, 2011, 10:31pm CDT by Reef Maniac

  Here's an interesting one:
  
  from the BBC World News...
  
  Quote:

  A satellite that will map the saltiness of seawater has gone in orbit. Data from the Aquarius/SAC-D spacecraft will help scientists understand better the processes that drive ocean circulation and the movement of freshwater around the planet. . . Scientists have been able to measure ocean salinity for decades by lowering instruments from ships or by deploying robotic floats, but the technology to sense this property from orbit is a recent innovation. Salinity is of interest to researchers because it is both a determinant of ocean behaviour and a tool to diagnose what might be happening in the climate system. Aquarius carries three high-precision radio receivers that will record the natural microwave emissions coming up off the water's surface. These emissions vary with the electrical conductivity of the water - a property directly related to how much dissolved salt it is carrying. Together with temperature, salinity will define water density, and density and wind are the wheels of ocean circulation - the means by which Earth moves much of the energy it receives from the Sun around the globe . . Our goal is to retrieve salinity at 0.2 parts per thousand," said Aquarius Principal Investigator Gary Lagerloef of Earth & Space Research in Seattle. "That's the equivalent concentration if you were to take a dash of salt about the same as one-eighth of teaspoon and put it in a gallon of water. That works out to about one millilitre of salt in six litres of water. That's the amount of salinity change that Aquarius will be able to observe from month to month over any part of the ocean.

  So, NASA, please check up on my tank whenever your satellite passes overhead - my house is the third one from the corner, the one with the big trees and the solar panel on the black tile roof, you can't miss it. Oh, and just send me an email if it needs topping up :whistling: :whistling:
  
  Hennie.
• 

  Control systems

  Posted: April 9th, 2011, 10:32pm CDT by Reef Maniac

  A new member (M247) has been communicating via PM with me during the last week, discussing control systems to be used in a marine aquarium. I suggested that he start a new thread to get other reefers' opinions on this as well, but he is still a bit unsure about posting here on MASA, and has asked me to set up a thread on his behalf. So, without further ado, here is our discussion so far - please feel free to comment/discuss this further, and join me in welcoming Martin and his wife to MASA :)
  
  Hennie
  
  Quote:

  Hi Hennie Me and my wife made the decision to chuck the TV and replace it with a 1,8L x 0,8W x 0,7D Reef aquarium. The tank is still in fabrication and we have some .let’s say difference in opinion about the location of the equipment:blush:. It would be great to have all the stuff outside in a shed of some sort and only the tank in the room. Best regards Martin

  Yes, that would be the ideal, but it is usually not practical.
  
  I'm not sure if you've seen the thread on my tank, but it would be an option to have everything either below the tank, and/or above the tank (like I did with the "crawlway"), and/or with a small "room" next to the tank to house the skimmer if it is a large one.
  
  Of course, IF you have the space in an adjacent room or outbuilding then that would take first prize...
  
  Quote:

  Do you perhaps know if it would be possible to check Ammonia and NO2 with a control system?

  Hi Martin.
  
  No, I am not aware of any control system that can monitor/control these parameters.
  
  For what it's worth, once a tank is stable (say more than one year old) it is not necessary to measure these parameters (IMHO), as the readings will remain "zero" as long as everything is OK. I would rather (and do...) monitor pH and ORP electronically, and regularly check alkalinity, calcium, nitrate and phosphate. The ORP is especially useful as an early warning system - once you get a reading range differing from the normal, you can haul out the ammonia and nitrite test kits to check if there really is a problem.
  
  Of course, with some experience one can usually tell by just looking at the tank and the inhabitants if something is wrong. I have not done a single ammonia or nitrite test during the past 4-5 years...
  
  My comments in blue:
  
  Quote:
  Originally Posted by M247
  Thanks for the help Hennie.
  
  So if we summarize the requirements of the control:
  
  · Control and measure Temp. Yes - vitally important, but fortunately the easiest and most accurate to do.
  
  · Control and measure PH Yes. the "control" part would be to regulate CO2 to the calcium reactor (stop when the pH drops below a lower limit of (say) 8.0) and the dripping of lime water (kalkwasser) (stop dripping when pH reaches an upper limit of (say) 8.4.
  
  · Measure conductivity Nice to have... You could add a "control" dimension to either add RO water of a concentrated brine solution to keep your salinity/conductivity constant (thus acting as an ATO), but in my opinion that just increases the risk of something going wrong.
  
  · Measure ORP Yes. This will give you a general indication of the tank's wellbeing, but should never be acted on in isolation. Also, don't chase numbers - compare the trend from any given day with the average past weeks/months.
  
  · Measure Dissolved Oxygen Nice to have, but expensive. If you are looking at your ORP then perhaps not really necessary.
  
  · Control the lights Yes. Very convenient, and adds stability to the tank (in nature the sun does not come up at 06:00 one day, and at 10:00 the day after a party...). Use good quality timers, and make sure that they are rated for an inductive load of at least 1.5x your load, else they tend to burn out pretty quickly (if, of course, you are using electronic timers).
  
  · Control the pumps Yes, but... Constant switching on and off of "normal" pumps will wear out their impellers pretty quickly, and should be avoided. Rather use pumps such as Polarios or the controllable Tunze pumps (but very expensive...)
  
  · And maybe automated water change. No. IMHO this adds another element for something to go wrong (pump not starting/stopping when needed, changing salinity/pH/temp etc. too rapidly...)
  I prefer to do partial water changes in person, and only after testing of the old and new water to ensure that all parameters match closely. This is also done as part of my maintenance routine, and the "old" water is obtained by siphoning out dirt and mulm, lime slurry used to kill aiptasia, cleaning around rocks, etc.
  
  This is an interesting topic - why don't you post it in one of the MASA forums - then you can get comments/opinions from other members as well.
  
  Regards,
  Hennie
  
  Quote:

  Hi Hennie Would you mind posting it? I’m still finding my way on the site and T&C of the site I would love to see the people comment on this topic and in the mean time I’ll read the T&C’s and keep you posted on the control system info I can find. Regards Martin

• 

  Christmas wishes

  Posted: December 24th, 2010, 7:17pm CST by Reef Maniac

  To all my Christian friends on the Forum:
  
  May you and yours have a very Blessed Christmas.
  
  Hennie & Family
• 

  Coral eating jellyfish

  Posted: October 9th, 2010, 7:16pm CDT by Reef Maniac

  Found this amazing article on BBC Earth News:
  
  Predatory coral eats jellyfish
  
  Here's a photo from the article...
  
  
  
  Hennie
• 

  Now THIS is an algae bloom...

  Posted: October 9th, 2010, 7:09pm CDT by Reef Maniac

  Found this interesting article on BBC Earth News:
  
  BBC - Earth News
  
  Quote:

  In late June 2008, the waters and shores at the Qingdao venue hosting the Olympic sailing regatta experienced a massive green tide covering about 600 sq km. Lasting over two weeks, it took more than 10,000 people to clean up, removing over one million tonnes of algae from the beach and coast... ...Within 10 days, these patches had moved away from the coast and into the Yellow Sea, covering 1,200 sq km, and impacting about 40,000 sq km of ocean, making it the largest algal boom, or green tide, ever recorded.

  Hennie
• 

  Hennie moving to Natal - well, sort of...

  Posted: September 13th, 2010, 8:38am CDT by Reef Maniac

  I will be looking after a construction project in the Natal Midlands for the next 5-6 months, and will be based near Nottingham Road. Although I will be commuting to Bloemfontein whenever I get the chance, that will not be all that often, and I will have to spend some weekends at my new place. My long suffering wife will stay in Bloem to look after my tank, and the cats, and the dogs, and the kids, and the garden, and...
  
  So, this gives me a good opportunity to meet some of you KZN fellows, perhaps attend one or two of your meetings, do some fishing (who's inviting ???), perhaps join you guys on a collection trip, and just generally get to know the Last Outpost of the British Empire a bit better.
  
  Hennie
• 

  Hennie visiting Cape Town

  Posted: February 27th, 2010, 1:18pm CST by Reef Maniac

  Hi Capetonians,
  
  I will be visiting Bellville next week, and will be staying at the Bellville Town Lodge on Tuesday, Wednesday and Thursday nights.
  
  If anyone would like to stop by for a "kuier" in the evenings I would be very happy to meet for a bit of reef talk, and perhaps even supper...
  
  I will unfortunately not have transport, so won't be able to visit further away...
  
  Hennie
• 

  Mini-MACSA, anyone???

  Posted: February 21st, 2010, 8:36pm CST by Reef Maniac

  Hi everyone,
  
  During our Central SA meeting at the Free State university this afternoon, the thought came up that we would like to arrange a sort of "mini MACSA" workshop/conference here in Bloemfontein.
  
  The idea is to start at (say) 14:00 on a Saturday afternoon, have some marine biology and chemistry lectures during the afternoon, have a braai the evening, have a few more lectures or discussions on Sunday morning and close at (say) 12:00.
  
  The biology department of the varsity will host us (venue), and they will be able to give lectures on fish diseases, micro flora, marine biology, in-depth discussion on DLSB's etc. They should also be able to persuade one of their chemistry department colleagues to give us a detailed discussion on the chemical processes happening in our tanks (calcium, alkalinity, nitrate, phosphate, etc.)
  
  I'm sure that we could persuade a few of our local (SA) gurus to chip in with an interesting talk or two - thinking here about Nemo's Janitor, Bob the Reef Builder, Alan, Mekaeel, Millepora, Leslie Hempel, Ed, Neil, Lanzo, etc. (What about a tank photography lecture from Ross, Rory or Sean ???) - who's volunteering???
  
  The idea is to have a more informal setup than the yearly IMACSA, and to not make any money out of this - purely for the enjoyment and advancement of the hobby as a whole, and to specifically boost the hobby awareness here in the Free State. The only cost would probably be for the Saturday evening braai, traveling, and for your accommodation on Saturday night. Even that can be minimized, however, as we are all prepared to accommodate people in our homes (Vrystaat gasvryheid...).
  
  So, what do you people say - good idea, or are we wasting our time...
  
  Hennie
• 

  Seriously macro

  Posted: February 14th, 2010, 5:14pm CST by Reef Maniac

  Check out this thread - you can't get more technical than this...
  
  
  
  Hennie
• 

  Starting With Marines

  Posted: February 6th, 2010, 3:12pm CST by Reef Maniac

  So, you want to start a Marine tank….
  
  A word of warning: starting a marine tank cause a serious change in human behavioral patterns - looking dreamy eyed at your tank for hours on end; phoning your loved ones (or anyone!) in the middle of the night to tell them about a new polyp, worm, glowing thingy about 1mm long, ... which you have just discovered; not buying new clothes, furniture etc. because your tank REALLY needs that new light, filter, ROCK, etc.... Oh well, maybe you won't get hooked so badly.
  
  Firstly, get some advice.
  
  

  • Most people’s main source of advice is the Local Fish Store (LFS). Pet shops, LFS's, call them what you like, these shops all exist primarily to make money. If they do, they are successful, and the owners can live in comfort (or even grow rich ??). If they don't make money, they go bankrupt. They will usually try to sell you the most expensive (often quite useless), items, preferably something which you will have to upgrade later (another sale for them...). And this could happen with some of the "better" shops - the really "bad" shops will also sell you incompatible livestock, or diseased fish, or even fish caught with poisons, knowing that they will die after a few days. They can then blame it on you (bad water quality, wrong filter..."you also need this UV sterilizer to reduce disease..." and because you are not sure yourself, you inevitably buy more equipment (usually also useless). Get the picture..?? So BUYER BEWARE!
  • People on Internet discussion groups do not have any financial gain by what they recommend, and are usually impartial, but there is another problem lurking - Pride. "I use skimmer xxx, or pump zzz, this is the best, use it!" "Oh, I've kept 10 types of Angels, and 4 types of Damsels in a 50 gallon tank for the past 5 years, It’s EASY - you can do it too..." or even worse, "Oh, I am very successful with keeping anemones. They are easy to keep, I've had 5 in the last year..."
  • Advice in books is usually outdated. Details on the animals and plants tend to stay relevant, but "technical" issues such as filters, skimming, lighting, etc. tend to change rapidly, as new equipment and techniques are developed. So, before you decide on anything technical, query what the books say! Whilst gathering your information, you must THINK. Is it logical, does it agree with what other books say, or with the views of "experts"? You must also get as many recommendations as you can, and then try to decide what is right FOR YOUR PARTICULAR SITUATION. Even some of the most notable "experts" on the net, some even with PhD's, can't agree on "what is right" all the time. They do tend to agree on the basics, though, so if you get some "way off" advice, you should be wary.

  Deciding on the TYPE of set-up
  
  Before purchasing ANY equipment, you should decide on what type of environment (or set-up) you want. Some may argue that a fish only tank is easier to keep, as fishes can withstand a greater degree of pollution and water quality fluctuations. A "reef" tank though slightly more difficult, is much more interesting, and gives one a greater sense of achievement and satisfaction. Many people start off with a FO (fish only), only to upgrade to a reef tank later. This invariably results in some equipment having to be replaced, because they did not buy "Reef quality" originally. I would like to suggest that you buy your equipment with a reef tank in mind, even though you may initially plan to keep only fish. Is "fish only" easier to keep than "Reef"?
  
  The general statement that "a Fish Only system is easier to keep" (or that "inverts are a lot harder to keep") is very misleading, and totally unfair to novice marine aquarists. Let me explain:
  
  Keeping "easy" inverts, such as some species of soft corals, cleaner shrimps, Featherduster worms, etc. are actually easier than keeping fish. They cause much less pollution, and therefore place less of a bio load on the system, which maker filtration a lot less critical. They don't get diseases such as "Ich", and many do not need much feeding either. You do need a minimum amount of light in order to keep corals and other photosynthetic animals. Fortunately the easier "low light" softies, such as brown or green Star Polyps (Pachyclavularia and Briareum spp.), Mushroom corals (Sarcophyton sp.) and Devils Hand or Finger Leather corals can be kept under normal fluorescent lights - though you would need quite a few tubes....
  The "difficult" part of keeping a reef tank is when you also want lots of fish in it. This just does not work very well, and is not to be recommended to newbies. Rather start off with a "marginal reef" tank, with lots of live rock, a deep live sand bed substrate (both very important elements of your filtration, as well as being interesting in their own right), some "easy" soft corals, some tube worms, etc. and only a few reef compatible fish.
  
  Do your research first, though. Learn as much as you can about the different filtration methods, compatibility of livestock, food and feeding, and everything else you can pick up... Then, carefully plan your set-up, and GO SLOWLY. In this hobby there is a saying:
  
  IN A REEF AQUARIUM, ONLY BAD THINGS HAPPEN QUICKLY.
  
  If you stock your aquarium before it has cycled properly, you will probably kill your animals. If you stock to rapidly, your tank will have another ammonia/nitrite spike, again probably killing your animals. At best, you will have problem algae, and sick fish. Remember that this is a long-term hobby. It is not uncommon for a tank to only stabilise properly after 6 months. Your corals can outlive you, and even the most common fish can live longer than 20 years, if you do your bit....
  
  Essential Equipment
  
  Equipment does not *have* to be very expensive, but it *usually* ends up costing a great deal more than you originally had in mind. Tank size and Shape:
  Although one could successfully keep very small marine tanks, this is a specialised field, and is not the ideal for a beginner.
  

  • Deeper tanks look more natural. They do require more intense lighting, though. They should also only have the same bio-load as a regular depth tank of the same surface area.
  • A larger tank will be more stable, and forgiving if something goes wrong. A small fish dying in a mature 100-gallon tank would probably not have any effect on the water quality. That same dead fish would most likely cause an ammonia spike, algae bloom and possibly further die off if it was left in a 20 gallon tank.
  • Your fish will be less stressed in a larger tank (if you don't over-stock), as there is more room to evade aggressors, and to allow each fish to have it's own territory.
  • It is also easier IMHO to use a surge device (wave-maker) in a larger tank. A 20 litre surge discharged into a 200 litre tank will cause a "tidal wave" to overflow the top. In a 500-litre tank the effect will be less than half, and in a 1000 litre tank it would probably not even cause a ripple.
  • A pre-drilled tank with an "overflow" weir is much better than a conventional tank with a siphon "overflow" to the sump. It allows for a much larger water flow, and is much safer to use, as there is no siphon that can "break" and cause the tank to overflow and/or the sump to run dry.

  The disadvantages of a larger tank are mostly financial:
  
  

  • It would cost a lot more to fill the tank, and to do partial water changes
  • One would require substantially more live rock, and sand, to achieve a decent looking, and properly filtered tank. As live rock and sand are amongst the most expensive purchases, a larger tank would increase the total cost most dramatically.
  • One would obviously want more corals, etc. This would be added to over time, so work on a constant, long-term drain on the wallet.
  • Practically, it's more difficult to reach all the "spots" in a large tank when you're doing maintenance and cleaning.
  • The greater amount of living creatures, and costly live rock, etc. increases the financial risk of losing a major investment if there is a long-term power blackout, the tank cracks, an outbreak of disease, or other disaster. This would cause you to consider the purchase of "back up" equipment, such as a power generator if you want to sleep well at nights.

  Lighting
  
  This will depend on the type of set-up:
  
  

  • "Fish Only" (FO) tank only needs enough light to view the fish comfortably.
  • If you use "Live Rock" (FOWLR) in your tank, then you should not have less than 2.5-3.0 W/gal (more is better).
  • "Soft" corals such as star polyps and mushrooms require about 3-4 W/gal (again, more would be better).
  • Hard corals, clams and anemones need a minimum of 6-8 W/gal, depending on the water depth.
  • Normal Output (NO) fluorescent lights are mostly used on FO or FOWLR systems, but can be used quite successfully on Reef tanks as well, provided one has the space to accommodate all the tubes. As an example, I have kept a Carpet Anemone in my marginal reef tank for more than 8 months, using 8 x 40W NO tubes on my 55 gal. tank. (I have since upgraded to Metal Halides)
  • PC (Power Compact) fluorescent lamps are nearly as bright as Metal Halides, and are quite suitable to keep all types of marine animals in all but the deepest tanks. They are quite expensive, though, and not always obtainable.
  • VHO (Very High Output) fluorescent lamps are "old technology", and are being superseded by the PC's or MH's.
  • MH (Metal Halide) lamps are the brightest lamps available, and nearly equal the intensity of sunlight. They are probably the most suited type of lighting for deep tanks, and for "Reef" type set-ups with light loving animals such as SPS corals, clams and anemones.

  The light "Colour temperature" is also very important. Water "absorbs" the longer wavelength light (the red, orange and yellow colour) at a shallower depth than the shorter wavelength light (green, blue and violet). If one descended from the surface of the ocean, the red light would disappear first, and the last light remaining at depth would be violet.
  
  Sunlight at the water’s surface has a colour temperature of 6 500K. I don't have exact figures, but I believe that the 10 000K light spectrum approximate a depth of around 10m (33') below the surface, and the "bluer" 20 000K spectrum is equivalent of light at a depth of about 20m (66').
  
  Because *most* corals live closer to the surface, 10 000K light would actually be more natural for them than 20 000K light. If one were to set up a "deep water" tank, containing species living at greater depth than that of a "normal" shallow reef, one would be better off to use the 20 000K lamps.
  
  The following links may explain this in more detail:
  
  Reef Tank Lighting
  Lighting
  Photosynthesis/Irradiance (P/I) Curves and Why They Are Important to ReefKeepers
  
  Filtration:
  
  

  • Skimmer - This removes biological waste before it can decompose into ammonia, etc, and thus lightens the load on the bio-filter. Do not skimp on the skimmer - buy the best you can afford. It is perhaps the single most important item you will buy, so rather get one rated at twice your capacity than get one which cannot cope.
  • In a lightly stocked tank live rock and/or live sand "biological" filtration is all that is required (apart from the skimmer, that is).
  • In a more heavily populated "fish only" tank, a Wet/Dry trickle filter is probably the best biological filter, though it will lead to a higher nitrate level than live rock filtration.
  • Canister filters are good "mechanical" filters, but they tend to produce an excess of nitrates in the tank.
  • Under-gravel filters should be avoided where possible, as they also produce unacceptably high nitrate levels.
  • A sump – get the largest practical tank, plastic container, etc, which will fit below your tank (or anywhere else that’s convenient). A sump is not really essential, but it does increase the total water volume, and allows one to keep all the ugly equipment (such as heaters, chiller, skimmer, and just about anything else) out of the tank. It is also a great place to make a refugium, and it allows for a more efficient gas exchange due to the tumbling action of the water flowing down into it.

  Fresh-water Filters
  
  

  • It is very important to use pure, unpolluted fresh water to replace evaporated water, and to make the salt-water used for partial water exchanges. Using ordinary tap water invariably leads to algae outbreaks.
  • RO (Reverse Osmoses) filters are the cheapest in the long run, and they remove 95% (or more) of the contaminants from the water.
  • DI (De-Ionisation) filters become exhausted quite soon, and need frequent replacement. This makes this type of filtration quite expensive. DI units typically remove 99% of all contaminants while "fresh".
  • One can combine the two, first using RO and then DI. This results in the purest water, but IMO is not really necessary.
  • One could also use a "hand held" water purifier, such as Nitragon, or a household unit such as the Brita filter. These units are actually small DI filters, and work quite well while fresh. Because of their small capacities they are quite expensive, though.

  Other equipment:
  
  

  • Heaters: Work on using about 2W/gal to raise the tank temperature 5 degrees F above the room temperature. (Thus for a 55 gal. tank you would need ~ 300W to raise the temperature to ~ 75 F if the surrounding temperature is ~ 60 F). It is better to use two or three smaller heaters than one large one. If a smaller heater fails on, it is unlikely to boil your tank, and if it fails off the other heater can still supply some heat until you (hopefully) discover the problem.
  • Air pumps: This is not normally needed if you have adequate circulation. It is good to have a standby unit for an emergency, though. I also use mine to aerate freshly made salt water used for partial water exchange.
  • Thermometer: Get an accurate glass or electronic one - those little "stick on" types are not accurate.
  • Hydrometer: These are notoriously inaccurate. Get a good glass type, and make sure you know for which temperature it is calibrated.
  • Pumps – Good water circulation is essential. Buy a good quality return pump (if you’re using a sump), and one or two additional power heads. . A "surge" device or "wavemaker" is a good addition, but is not essential.
  • Live rock - get about 20% - 40% of the tank's volume of live rock. This is essential for long term water stability (read: low nitrate level).
  • Sea salt – There are many makes of salt, and not all of them are good. Read the package label, and ask questions on the Net before you buy it. You will not only need salt for the initial makeup, but also for regular partial water changes (about 10%-20% of water volume every 2-4 weeks, depending on stocking level, etc).
  • "Incidentals" – You will need some test kits, additives such as buffer and calcium, a fish net, some containers to mix your water…

  Tank "Cycling"
  
  To be honest, whenever I hear this term, I envisage this large, all glass tank, riding around on a bicycle …..
  
  The term "cycling" is actually a bit of a misnomer, IMHO. In our hobby, it usually refers to a state where the aerobic component of the filtration system has "matured" to such an extent that there are enough aerobic bacteria present in the system to convert the ammonia/um generated by the tank's bio-load into nitrite, and the further conversion of the nitrite into nitrate. In actual fact, this only completes of the first phase of the actual nitrogen cycle.
  
  Until a few years ago, that was as far as the process could go, resulting in a slowly increasing level of nitrate, which could only be reduced by partial water changes. Thanks to the "discovery" of live rock, and later of live sand, the "'cycle" can now be completed by anoxic bacteria living in these substances, further converting the nitrate into inert nitrogen gas.
  In hobbyist’s terms, a new system is considered to be "cycling" when there are still detectable levels of ammonia/um and/or nitrite in the water. A system is considered to have "cycled" when these levels drop to zero, and the nitrate level starts to increase.
  
  The important thing to remember is that a tank does not "cycle" only once. The system will reach equilibrium, where there is enough aerobic bacteria living in the filters to maintain an undetectable level of ammonia and nitrite with a given bio-load. Any increase in the bio-load, such as when a new fish is added to the tank, will upset this equilibrium, by "flooding" the system with more ammonia/um than the bacteria can digest. Obviously, with more "food" available for these bacteria, they will multiply (assuming that food was the limiting factor), and in time the system will reach a new equilibrium, able to handle this increased bio-load. This does take time, though, and in the meantime the increased level of ammonia and/or nitrite could be poisoning all the fish.
  
  How to "Cycle" a new tank.
  
  In order to "cycle" a new set-up, one must introduce a source of ammonia/um. In the past, this was usually done by adding some hardy fish (usually Damsels) to the new tank. Although this works very well in a bare tank (with outside filtration), it’s not recommended for two reasons:
  

  • It is cruel to keep any fish, no matter how "hardy" in water containing near toxic levels of pollutants.
  • Damsels are very aggressive, and once the tank has "cycled", they consider the whole tank as their exclusive territory. They will attack, and possibly kill, any new fish being introduced to the tank. To make matters worse, the rock in a typical reef tank makes it hard, if not totally impossible, to catch them when you eventually decide to replace them.

  I would start the cycling by initially only adding the sand. Let it settle for 2-3 days, with all the circulation going. Then, add one or two pieces of base quality live rock, and one or two dead prawns or cocktail shrimps (the food type, not a dead one from a LFS - that could be carrying any number of diseases!). At this time, start testing the water for ammonia daily. You should notice an increase in the reading, and after a few days, the reading should stabilise, and then slowly start to drop (this could take 1-2 weeks). At that stage, start testing for nitrite as well, and keep on testing for ammonia. You should now notice an increase in nitrites, and a decrease of ammonia. After another week or so, the ammonia level should be fairly low, and the nitrite level should have reached it's peak.
  
  Once the nitrite level has also started to drop, you can add the rest of the base quality live rock, and once both the ammonia and nitrite levels have become unreadable low, you can then add the good quality live rock (containing many interesting inverts). This could cause another ammonia & nitrite "spike", although it will be much smaller than the first. This is not critical if you’re patient - just let the tank settle for another month or two before adding fish. This should give the macro algae and small critters on the LR time to recover, and to multiply to sustainable levels in the LR, and to migrate into the sand. During this time, you should also add some live sand, and/or some live sand "starter kits" and "reef janitors". Also, don't be concerned with the initial algae growths - it's quite normal to have some diatom, cyano, and hair algae growing as the maturation progresses.
  
  "Cycling" a new system with uncured live rock.
  
  Introduce the LR after the tank's been up about a week, and use it to cycle the tank. Wait at least two months before introducing the first fish.
  
  Advantages:
  
  

  • You don't stress (or kill) any fish, and do not have to add fish that you will have to remove at a later stage.
  • You don't need to buy fully cured LR. In fact, the cheaper, uncured LR causes a better cycle, and usually have more diverse life forms in/on them.
  • You can introduce all the rock at once, do your "rockscaping", and have the tank completely set up when introducing the first fish.
  • You will have amazing growth of whatever comes on the LR - with no fish to eat them, you will get all kinds of macro algae, featherduster worms, soft polyps, even some corals, growing.
  • You will also enable the "small life", such as copepods and amphipods, to establish and multiply to such an extent that they should survive predation by your fish. Obviously, if you only have 2 or 3 of a specie to start off with, and they're eaten by a fish on the very first day, none will multiply after that.

  Disadvantages:
  
  

  • You will have to wait before you introduce any fish.
  • Because the initial bio load was smaller, you will have to add your fish at a much slower tempo to avoid causing another ammonia/nitrite spike.
  • You might have some algae growing on the LR. This is usually not a problem, though, as you start off with a nutrient poor set-up, which can be easily maintained, as there are no fish to feed. Also, the growing macro algae compete for nutrients, thereby restricting the growth of nuisance algae.

  Deep Live Sand Bed filtration:
  
  A general rule of thumb is to have a 4" layer of fine, graded sand, although the actual thickness would depend on the size of the sand. The finer the sand, the less water flow is possible between the particles, and the thinner the layer needed to achieve an anoxic zone in the sand. IMHO the very small size sand, though "perfect" for nitrate reduction, is not what occurs naturally, and does not allow hiding places for many small critters. My sand bed is made up of ~75% natural sea sand (shell grit and silicon sand, ranging from ~0.5mm to ~ 6mm in size)) and ~25% crushed coral sand (approximately 1-2mm in diameter). I have found that the areas containing the coarser particles have a greater abundance of small critters.
  
  Here are some links to interesting articles (hope they still work...):
  
  [sites.netscape.net]
  Reefs.org: Where Reefkeeping Begins on the Internet - View Document
  reefkeepers.org
  The page cannot be found
  The page cannot be found
  404 Not Found
  Reefs.org: Where Reefkeeping Begins on the Internet - Error Message
  The how and why of Deep Sand Beds
  The Quantitative Comparison of Two Nutrient Removal Systems
  
  Using Additives:
  
  It's quite human to want to add all kinds of things to help our creatures. The manufacturers and shops know this, and make a lot of money out of this "weakness". Unfortunately, many of these "snake oils" are just expensive water (perhaps coloured). Others do add trace elements, but an excess of many of these elements are actually detrimental to your tank (amongst other things, it tends to make cyano and hair algae grow...).
  
  Under normal circumstances, one should only add buffer (to keep the alkalinity up), and a calcium supplement if/when there are hard corals (LPS or SPS) or other calcium using life forms in the tank. Either use one of the "balanced" two-bottle supplements, or add Kalkwasser. If you do not have many calcium absorbing animals (such as corals), then you probably don't need to add calcium supplements. You then also don't need those high calcium levels normally quoted for a reef tank.
  Note that the long-term addition of calcium chloride will result in a gradual increase of the chloride content of the water. This will eventually result in your water's chemistry being quite different from that of natural seawater, which is not good at all. Apart from this, I would not add any supplements unless I could test for it, and found a deficiency, as regular partial water changes would replenish the trace elements used up by the inhabitants.
  
  I realize that I've only skimmed the surface of starting with this great hobby (pun intended), but I hope that this article can be of some use to someone out there…
  
  Article © Hennie Landman
  
• 

  Deep Sand Beds (DSB)

  Posted: February 5th, 2010, 6:16am CST by Reef Maniac

  Deep Sand Bed (DSB)
  
  The correct term should actually be a Deep Live Sand Bed (DLSB), because the sand bed can only operate properly if it is populated with appropriate sand-living organisms. But I'm jumping ahead of myself, so lets start at the beginning...
  
  Aim of a DLSB
  
  The aim of all filtration systems is to reduce potentially toxic biological waste produced by our tank inhabitants to less harmful, or even better - totally non-toxic, products. In our tanks the waste from our fish and corals, and uneaten food, is quickly converted to ammonia/ammonium (depending on pH), which is highly toxic even in very low concentration. Aerobic (oxygen loving) bacteria in the tank can fortunately convert this ammonium into less toxic nitrite, which other aerobic bacteria then further converts into nitrate. Although nitrate is not very toxic for fish, it does have the potential to cause massive algae blooms, and is still rather toxic to corals and other invertebrates. Unfortunately, this nitrate can only be further broken down by anaerobic bacteria, which only live in areas where the oxygen level is rather low (but not totally absent...).
  
  Both the aerobic and anaerobic bacteria need two things in order to multiply - enough food (the waste products) and enough suitable substrate "living space" (the rock or sand). In our natural filtration systems, we use live rock and/or live sand to act as substrate for both the aerobic and anaerobic bacteria. Because of it's size, a given volume of fine sand has a much larger surface area than the same volume of rock, and can house much more bacteria than the rock - thus making a sand bed a *much* better filter substrate than live rock.
  
  Aerobic area
  
  With good water flow in the tank, the surface of the sand bed (and live rock) continuously receives highly aerated water, and this water can slowly permeate into the sand bed (and into the interior of the live rock). This water is rich in oxygen, and readily supports a dense growth of aerobic bacteria which then uses the oxygen to convert the ammonium to nitrites and then to nitrates. During this process the oxygen is used up, and as the water moves further into the sand bed or rock it becomes more and more anaerobic (oxygen poor). At some depth, depending on the grading of the sand and the flow of water above the sand bed, the oxygen concentration in the water drops to a level where anaerobic bacteria can live and multiply, and where they can then convert the nitrates (which are in solution in the permeating water) into inert nitrogen gas.
  
  Anaerobic area
  
  As stated earlier, our anaerobic bacteria live in oxygen poor water - but importantly, they still need *some* oxygen. As a sand bed becomes deeper still, the concentration of oxygen can decrease to a level below where these anaerobic bacteria can live and multiply - this is the so-called anoxic region, and it is inhabited by anoxic bacteria. These bacteria "breathe" sulfur, and in even more anoxic regions they can actually "breathe" calcium (but the latter only occur at really great depths in the oceans, and I have never heard of them living in our tanks...). Despite the old-wives tales and "mythology", these anoxic bacteria are actually very beneficial to our systems, as they not only convert nitrate into nitrogen gas, they also convert toxic heavy metals into non-toxic (and less soluble) metal salts.
  
  Hydrogen Sulphide
  
  "OK", you may ask, "but what about the toxic hydrogen sulphide gas and black areas in the sand?" Well, hydrogen sulphide IS pretty toxic if released into the water in a large volume. Fortunately, when a DLSB is operating properly, this gas is used up again by some of the bacteria, and/or is continuously released into the water in very small quantities which is totally non-toxic. It is only when the sand bed is "stirred" by either the aquarist, or by a large "sand sifting" fish or other animal (which should not be kept in a DLSB tank in the first place...) that there is a chance of a toxic gas release.
  
  Contrary to popular belief, the black areas in the sand are also NOT indications of hydrogen sulphide production. The H2S gas is colourless, and can not turn the sand black. The black/brown/darkly coloured areas are actually caused by the anoxic bacteria converting metals, such as manganese (black), iron (red/brown), etc. into harmless manganese oxide, iron oxide, etc.
  
  Life in the DLSB
  
  "Right, now what about the "Live" in the DLSB?" The deep sand bed needs a constant, but very light, water flow through it, from the surface right down to the deepest part of the bed. This is achieved by the "pumping" and "crawling" action of the sand-living organisms in the DLSB. A mature, well-operating DLSB has literally thousands (if not tens-of-thousands...) of sand-living creatures, ranging from large polychaete (bristle) worms all the way down to microscopic flat worms, amoebas (if there are salt-water amoebae??), etc. in every cubic centimeter of sand. All these "critters" continuously move around in the sand, and the larger worms also "pump" water through their bodies whilst feeding (or breathing), and although each individual movement is quite insignificant, the total movement of all the critters can displace (and circulate) a surprisingly large volume of water.
  
  A second reason for needing sand-living organisms in our DLSB is that they EAT. The larger worms would eat fish excrement, left-over food, and other "waste". Their waste is then eaten by the smaller copepods, whose waste is in turn consumed by micro flat worms, then by the single-celled organisms such as the amoeba... and so it goes all the way down the food chain, until the "waste" has been converted into nice "bite-size" portions for the bacteria.
  
  In summary
  
  To summarize - a successful DLSB needs the following: Properly graded, fine sand with all the particles having smooth, rounded surfaces - in other words, a "natural" sand such as real sea sand, river sand, etc. and NOT crushed sand (which have sharp edges due to the crushing process...). A total depth of between 75mm and 300mm, with the most recommended depth being between about 100mm - 150mm. A proper "seeding" with either live rock, or preferably live sand imported from a reef with many of it's critters. It is also a good idea to swap small amounts of sand with other aquarists, as this can increase the bio-diversity in the sand. Good water movement over the surface of the sand bed. No sand sifting fish or other creatures, and NO siphoning or stirring of the sand bed by the aquarist.
  
  This has only just "skimmed" the surface of having a successful DLSB, but I hope that it has been of some use in clarifying this very interesting subject.
  
  
  Hennie
• 

  Photography tutorials - post your links

  Posted: January 23rd, 2010, 4:49pm CST by Reef Maniac

  Hi all,
  
  I've just come across some excellent "how to" articles, and thought that it would be a good idea if we all shared our favorite "links".
  
  To start with...
  
  Macro photography:
  
  dalantech's Gallery
  
  MACRO SHOOTING - Tips & Tutorials - Digital Grin Photography Forum
  
  Hennie
• 

  Slow international internet access

  Posted: January 22nd, 2010, 6:27pm CST by Reef Maniac

  FYI, just received from Hetzner:
  
  Quote:

  Loss of international connectivity attributed to SAT-3 cable Hetzner customers, together with most SA Internet users, are currently experiencing severe international connectivity problems since Wednesday, 20 January 2010. This means that browsing to international websites and receiving email from international sources has proven problematic. This issue is a result of a SAT-3 cable break on the London-Bellville link which continues to cause slow international connectivity. Hetzner is not able to anticipate or prevent issues relating to international connectivity accessed via the SAT-3 cable. Your local access partner or ISP (e.g. M-Web) gives you access to international bandwidth and it is this connectivity path that has been compromised by the SAT-3 cable break. Telkom SA is conducting major maintenance on the fault, with the maintenance window running from 20-22 January and again from 29 January to 1 February. During this maintenance window, most South African Internet users will experience intermittent high latency to international locations.

  I noticed that my email is very slow...
  
  Hennie
• 

  What photo editing software do you use

  Posted: January 19th, 2010, 9:43pm CST by Reef Maniac

  I have been spending some time doing research on the various photo editing software available (both commercial and free), and would appreciate your comments and advise on this topic.
  
  I'm currently using the software which were bundled with my camera, that being Canon's Zoom Browser, and (mainly) DPP. I also have a copy of Adobe Photoshop Elements 2, which was bundled with a scanner that I bought many years ago, as well as the free Picasa 3, which I use for photo filing and sorting.
  
  So far, I have been getting along pretty well with this software, doing all the post-processing in DPP, except for file cropping and resizing, and the infrequent cloning/painting out of dust marks, etc which is done in the old Elements 2. I've recently started to convince myself that I need a software upgrade, but I'm not totally convinced that paying R9 000.00 for the latest Adobe CS4 is the answer either :whistling:
  
  I have just downloaded the latest version of Gimp, the GNU freeware graphics program, and after playing around with it for the last hours or so I'm rather impressed with it. I've also downloaded a very nifty little program called BorderMaker (another freeware program), which makes resizing photos (and adding borders, if wanted) a breeze :thumbup:
  
  The biggest weakness of these freeware programs (from my limited research) is that they are not supported with many tutorials, whereas there are numerous books on the various versions of Photoshop, and I'm pretty sure that CS4 can do a hell of a lot more than Gimp (but do I need it...).
  
  So, please, let rip with your opinions and advise...
  
  Hennie
• 

  Chaotic water movement

  Posted: January 11th, 2010, 9:34pm CST by Reef Maniac

  Here is a short video (not very good quality, I must admit...) showing what I consider to be "chaotic" water movement in my tank. This chaotic water flow is achieved by combining three power heads, my sump return via an over-head manifold, and a Polario 22ML set to alternate at 15 second intervals. The leather coral shown in the video is pretty huge, measuring about 450mm in diameter, and standing about 500mm high. It is placed about 300mm from the right edge of the tank, but the water flow is pretty much the same throughout the tank (obviously higher close to the Polario).
  
  Anyway, this is my first video link, so I hope it works...
  
  Hennie
  
• 

  Uploading and viewing video

  Posted: January 11th, 2010, 5:25pm CST by Reef Maniac

  Hi Everyone,
  
  I have recently tried my hand at taking some video clips of my tank (nice yuppie feature on the Canon 5D Mk. II :biggrin:) - I would love to post these videos somewhere, to allow our members to see what a decent surge should look like :whistling:
  
  Can anyone please explain what/where/how I should go about doing this.
  
  Thanks,
  
  Hennie
• 

  Developing the digital negative (how much is just enough...)

  Posted: January 8th, 2010, 11:54am CST by Reef Maniac

  Let me start off by stating that I'm NOT a digital photography boffin, and that I'm trying to advance my digital skills, especially with post-processing.
  
  We had some discussion on this topic on another thread, and I thought that it might be a good idea to post some photos showing what I do to "process" my digital "negatives" - the RAW files as recorded by the camera.
  
  I really would appreciate comments on the following processes - how far is enough, what is too much... (Please just bear in mind that most of us have uncalibrated computer monitors, so what looks more green on my monitor might just look more yellow or blue on yours... Looks like I will have to get myself a Spyder calibrator real soon, if I want to be serious about post-processing...)
  
  Anyway, here are the photos, each with a short description on what I've done to that particular photo. All post-processing was done using Canon's DPP software, supplied with the camera, and the images were then captured to my computer with the "print screen" function on the keyboard, converted to .jpg using Microsoft's Paint program, so the over-all quality is not so good...
  
  1: This is the original RAW image, without any corrections/adjustments. As can be seen from the histogram graph on the right, the photo was somewhat over-exposed
  
  
  
  
  2: My first step in processing the "negative" was to adjust the left-hand "slider" of the histogram until it was close to the start of the graph. This shifts the exposure, removing that portion of the image where there is no "dark" information. this results in the image becoming darker, but showing more detail in the darker (shadows) parts of the photo.
  
  
  
  
  3: The second step is to move the left-hand "slider" to remove the lack of data on the bright side of the image, resulting in the image becoming brighter, and revealing more info in the highlights.
  
  
  
  
  4: The next step involved a slight adjustment of the contrast slider (increasing contract by "2", as well as a slight reduction in the over-all brightness, by moving the "brightness slider" to -0.33
  
  
  
  
  5: The next step involved the adjustment of the "color tone" and "saturation" sliders, until the colors looked more vibrant and natural. (I probably over-did this a trifle...)
  
  
  
  
  6: The final step was to tweak the "S-curve levels" in the RGB tab slightly to enhance the green color of the anemone, to make it look closer to what it looks like when viewed with the naked eye. To achieve this, I slightly increased the green (G) curve, and slightly reduced the red (R) curve.
  
  
  
  
  And here is the final crop, reduced to 800x700:
  
  
  
  Hennie