PH/GH/KH alterations

Question
QUESTION: I am trying to breed Hypancistrus Zebra at the moment but am having a few problems with getting the PH, KH and GH right.

Do you know of any products that will increase/decrease the PH that will not affect KH or GH? And likewise the same for GH and KH?

I have peat but while it lowers the PH it also softens the water, which I don't want. Baking soda hardens the water, but also increases the PH, I think, and I don't want that either. Do you know of anything that can raise or decrease these two parameters without affecting the others? I've heard Almond leaves decrease PH, but do they also affect GH?

I've tried using Nutrafin PH down but it seems to be having little affect. My KH is 5 so I am wondering if it is merely buffering its capacity to lower the PH or not.

Currently my parameters are: 7.4 PH, 7 GH, 5 KH.
Whereas at the moment I am aiming for 7.0 PH, 10GH and 5/6KH.
For breeding purposes the parameters have to be quite exact.

Thanks for your help

ANSWER: Hi George,

From my experience, most pH lowering products will affect the KH/GH in a minimal way.

The reason why your pH chemical is not working is because your aquarium has the buffering ions in it, which automatically adjusts the pH back to it's normal level. (7.4, in your case) No matter what chemical you use, the buffers will most likely bring it back up. The way to solve this is by removing the ions, through a tap water filtration unit or other filter. These units will remove those ions, and so you can change the pH more easily.

Adding calcium carbonate will increase both GH and KH slightly. (CaCO3)
1/2 Teaspoon per 100 liters will increase both by 1-2 dh. It should not affect the pH, and the pH can be lowered separately.

Good Luck, and Happy Fishkeeping!

---------- FOLLOW-UP ----------

QUESTION: Great answer:)

So calcium carbonate will increase GH and KH without affecting PH.

If I use peat in my tank to lower the PH it will also slightly lower the GH, I think. But if I use Calcium carbonate in conjuction with peat, will it raise the GH alot quicker than the peat will decrease it, while the peat can lower the PH?

What about Almond leaves? Will they lower the PH quicker than peat, without affecting the GH?

Thanks again.

ANSWER: Hi George,

Calcium carbonate should not affect pH.

Yes, your theory should work. Calcium carbonate will increase the GH faster than the peat can lower it. Peat only lowers the GH in a minimal way. That sounds like an excellent idea.

Almond leaves, like driftwood, produce tannic acids, which lower the pH and make the water slightly yellow. However, the carbon in your filter will take care of the yellowness. I'm not sure if the affect the GH, however. Try it out!

Good Luck, and Happy Fishkeeping!

---------- FOLLOW-UP ----------

QUESTION: I have been looking round my local chemists but they say they no longer use calcium carbonate anymore and recommended trying to get it from an aquatic store. I contacted my local Maidenhead Aquatics and they said this is the stuff:

TMC Bio-Calcium

Its a calcium additive for marine systems. However isn't it also Calcium Carbonate? I think aquatic stores will only sell it under a marine catagorisation though as its not commonly used in freshwater, but is this the stuff I need?

Thanks again:)

Answer
Hi George,

Personally, I've never used that brand before, but I think that it's calcium carbonate. It's true that it's mainly used in marine aquariums. Most freshwater aquarists don't need to use calcium carbonate, because GH and KH are not as important in freshwater than saltwater.

Read the label of the product. Other than the brand name, it should have an ingredients list or one ingredient. As long as it says "Calcium carbonate" (CaCO3) somewhere on the product, you can use it.

Good Luck, and Happy Fishkeeping!