How to increase KH (2-4 currently)

[rjsomers]

I want to know what I need to do to increas the KH in my tanks. It is too low for optimal pH stabilization and all other parameters in the tanks are stable - including pH.

Thanks

[randy]

http://www.dataguru.org/misc/aquarium/calKH.asp

[sharuq1]

That method works even better if you use baked baking soda. Just throw it in the oven scattered over a cookie sheet at 400F for an hour. This drives of the excess water and CO2.

[roypark05]

One solution that can be a very stable and permanent fix, but requires some time, is adding pieces of marble in amongst your gravel. The marble slowly adds calcium/carbonate hardness from gradual dissolving.

[rjsomers]

I think this is why i used crushed oyster shells or Coral in my previous years. Does that make sense?

[jvision]

Yep, adding shells will help buffer your water.

[roypark05]

Yeah same thing as the marble. Both dissolve as CaCO3 (calcium carbonate, the basis of KH)

Edited August 20, 2009 by roypark05

[werner]

Do you want to increase general hardness, or just the KH [carbonate (CO₃^2-) or bicarbonate (HCO₃^-) ions]?

The carbonate in CaCO₃ increases KH, but the calcium also increases the general hardness.

Baking soda (NaHCO₃) will increase KH only.

Edited August 20, 2009 by werner

[rjsomers]

I am only looking ot increase my KH. GH is looking good.

Any fish that are more senstive to using baking soda?

My list is in my signature.

Thank-you everyone for your help.

[randy]

Hagen makes a product called Nutrafin PH Stabilizer this will raise kh

[werner]

I don't think you'll be adding enough baking soda to make a difference for the fish. Just don't add it dry or they'll try to eat it.

[jewels]

Do we factor by 17.9 to find ppm? Even 4 X 17.9 would get you only 68 ppm kh. Is this typical of Calgary water?

[Parachromis1]

Only one product I would add. Kalkwasser solution. It's lab grade as well.

[jvision]

Kalkwasser is actually a CaCO3 product, so it's similar to adding shells/dolomite/coral.

[werner]

Do we factor by 17.9 to find ppm? Even 4 X 17.9 would get you only 68 ppm kh. Is this typical of Calgary water?

Nope, not typical. The Calgary Water Quality Report lists the carbonate hardness as anywhere from 140-259mg/L. There's plenty of buffering capacity right out of the tap.