Understanding Calcium Carbonate…
I stumbled upon a forum in which copy pasted an article there by Willam Wurts, a PhD in aquaculture at Kentucky State University. In the article, William Wurts agreed upon the importance of CACO3 for Koi and also mentioned that even though Japanese Mud ponds have low TDS, the Koi can still get their needed dose of Ca++ directly from the mud. This is not so for our Koi ponds, thus we must supply artificially Ca++ thus compromising a bit on TDS (this part is my conclusion). The link to this post is here http://www.koiphen.com/forums/archive/index.php/t-52088.html..
But then again Ca++ is a cation, so even though I do put in some CACO3 in my pond, and dissolves some Ca++, wouldn’t it just be absorbed by the BCB’ before reaching the Koi? This then again reminded me about another question you once asked me about the stability of my pond/AFS when I add some clay to it, a question which till now I don’t understand, especially on what was the stability questioned moreover how to measure it. But rather me asking the wrong questions, may I ask your opinion about this CACO3 towards Koi development and its compatibility with the AFS?
Most Koi foods have an added supplement like calcium in their ingredients and some cat litter clays also have Calcium Carbonate (CaCO3) in them already. However, I can see your concerns about adding Ca++ to your pond and is the BCB’ absorbing that added calcium and taking it once again out of solution. The simple answer would be no, but then that would not be giving you the whole representation of the whys. You are introducing through a clay additive Ca++ to your pond and so far it has been working I take it? It sounds to me that you are trying to add more Calcium to your pond because your water is soft or under the recommended 63-250 mg/l of CaCO3, is that right?
I see on that forum you recommended to read that Roddy, one of the posters, is misinterpreting the information given by the Agricultural Ph.D. and makes the statement that, Quote: “Below 100-ppm the fish will suffer unless they are in a mud pond where they can eat mud and get calcium from it. Unfortunately, some of the current pundits in the hobby confuse mud pond water parameters with our back yard Koi keeping, and that is a mistake that costs some folks their Koi coloration and growth rate from keeping the GH below the minimum requirements.” This statement is painted with a very wide paintbrush and encapsulates under the same umbrella that Koi food, make up water from evaporation and water changes have no effect on our Koi’s growth and coloring or the adding of Ca++ back into the system?
Cyprinidae or cyprinids is the largest family of fish with about 2400 species and can take a diverse range of water conditions with no ill effects, which also includes low Calcium salts too, like in Japanese mud ponds. In the wild were water is low in calcium carp eat snails, crayfish, tadpoles, and bivalves and all these foods will supplement the fish with calcium when salts are too low in solution and they still can grow to become the monsters of the lake.
I doubt very seriously that the Koi in Japanese mud ponds are only getting their Ca++ supplements from eating the clay off the bottom of mud ponds as stated by Roddy with no other additional food supplements. Once again we're back to misinformation to the hobbyist and for those that are new to the hobby may even take it as presentational fact. I know for a fact that when I was in China, fish farms made their own foods and added vitamins and minerals to help supplement their fish’s diet for optimum growth, so why not the Japanese do like whys. I use Purina Game Fish Chow Food for ponds as I have mentioned before and some of the ingredients included in the food are Calcium Carbonate, Calcium Pantothenate, and Calcium Iodate the same as the Chinese fish farms use along with the Japanese fish farms too. These additives to supplementary fish foods are why the Japanese and Chinese fish farms keep their TDS, GH and KH so low. As stated by Purina and Quote:
- Multiple Size Particle - feeds all sizes of fish
- Floating ration - great for viewing
- Higher digestibility of nutrients
- 32% high protein with attractant
- Added Vitamin C to reduce deficiency-related problems
- Enhances production of forage fish to enhance size and number of bass
|Purina Game Fish Chow Food for ponds: Some of the ingredients included in the food are Calcium Carbonate, Calcium Pantothenate, and Calcium Iodate.|
The Agricultural Ph.D. that wrote the article knows that all fish farms and agricultural fish food farms add Calcium Carbonate to their foods so keeping the water at a high GH is really not needed if the Koi or game fish are supplemented with additional foods (Which they are!) that will help bone development and growth. When I was in Israel, Israeli Koi farms also did the same thing by supplementing the diet and not so much the water.
Koi and Goldfish forage in the mud or bottom sediment by sifting through it for food that I mentioned above by constantly taking it into their mouths and spiting it out, but they don’t eat it directly but indirectly, not as Roddy has stated. So, adding additional Ca++ to a pond is nothing new in the Koi hobby. Cyprinidae didn’t become the largest backbone species on the planet because they were touchy little animals and didn’t know how to adjust to water parameters that weren’t perfect in the eyes of us humans!
The addition of Calcium Carbonate is nothing new in the Koi world and one such additive that I have seen even by professional Koi keepers are that of Oyster Shells. Oyster Shells like that of Hen eggshells are mostly made up of Calcium carbonate and by adding them to the ponds mass they will disintegrate and add Ca++ back into the system…at least in theory that is. Now depending on what side of the fence you’re on, most say they do nothing and some say they do. But it takes chemistry to unravel this mystery on why some say they do work and others say Oyster shells are useless placebos at raising the GH or adding calcium to ponds!
Oyster shells and eggshells will not disintegrate back into salts unless the water is more acidic than alkaline in nature. The acidic pH is what does it, which is a pH of 6.0-6.5 will do just fine at breaking down the calcium from the shells. This would probably explain why it would work for some hobbyist, those with lower pH and not for others because it is pH dependent. Like that of Calcium Reactors used in saltwater aquariums, the pH is driven down by pressurized CO2 and Aragonite is used as a medium in the reactor to be broken-down for its Calcium content and trace elements. However, the Koi hobbyist is not using a reactor but just placing a bag of the Oyster shells in a waterfall hoping that it will add Ca++ back into solution. You add it by the clay additive and others do it by Oyster shells. Your way of adding Ca++ to your pond will give you better results than the iffy Oyster shell game though.
There is another way of adding pure Calcium Carbonate (CaCO3) back into solution that only some know of and for the life of me I don’t understand why it’s not used more often in the supplementation of Calcium if needed. The purest form of Calcium Carbonate in the world is something that we all grew up with as children and probable don’t even know it…chalk! Yes, blackboard chalk is the easiest obtainable of all Calcium carbonates and chalk is inexpensive! By placing the chalk in a mesh bag and then placing it by the inlet diffuser of your AFS or in front of any outlet tube, it will then break down the chalk back into solution once again and elevate the calcium salts of your pond. It is not pH dependent like Oyster shells and eggshell are, and is guaranteed to work. I remember doing a seminar for a saltwater club and told them about the benefits of chalk in reef aquariums and they all though I was crazy because it was too cheap and if the Calcium Carbonate didn’t come from a bottle or reactor it just couldn’t be true! I use to place chalk in my filters sump to my saltwater invertebrate tanks and it worked just fine.
If you wish to give your Koi the benefits of Calcium because your food does not have it as an additive, then you're stuck with supplementing it by other means. But make sure it is not in your food fist so your animals’ don’t get an overdose of calcium, which is bad for them like it is for humans. So if the food already has Calcium in it then it will not be attracted to the BCB’ and stay in the Koi until expelled by the animals latter.