# kH vs DH



## jsm11482 (Aug 8, 2006)

Are the terms kH and DH used interchangably?


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## Lupin (Aug 2, 2006)

PM sent, mate.








GH/DH=general hardness
KH=carbonate hardness


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## girlofgod (Aug 22, 2006)

are the kh and alkalinity the same thing? cuz my mother has a 5-n-1 test strip and on hers she said that it has a reading for KH (total alkalinity)...is that right? or did she misread it?

bri


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## Lupin (Aug 2, 2006)

No, alkalinity is part of the pH. When pH is above 7, then it is considered as alkaline. Lower than 7 is acidic. 7 is neutral.
KH is simply a carbonate hardness. To increase it, simply use oyster shells packed in a stockings and place it in the filter. If not, try using sodium bicarbonate and try to monitor the level. To lower it, use RO water,peat, etc. There are several ways of lowering the KH.


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## girlofgod (Aug 22, 2006)

how do you test for it? and how imporatant is it? i cant seem to find a kh test kit anywhere...


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## Lupin (Aug 2, 2006)

API Master Test Kit has one though it lacks ammonia test. It's important to test it. Below 3 KH may result to pH crash although fortunately, it isn't common. It happens more easily when using CO2 for plants.
Maintaining a KH of 3 or above is important to avoid the possibility of pH crash which can kill several of your fish.


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