View Full Version : GH and KH
JohnMemorialHS
12-21-2002, 6:20 PM
which one of those is responsible for flunctuating pH?
goldfish freak
12-21-2002, 6:22 PM
KH.
Sumpin'fishy
12-21-2002, 6:22 PM
KH. From what I understand, GH has little to do with alkalinity. Anyone wanna correct me?
GH is hardness, as when a fish is said to be a soft-water of hard-water fish.
KH is buffering, carbonate hardness, or alkalinity.
Mr.Jingles
12-21-2002, 10:31 PM
really? so, the KH just determines what the pH will hover around? wouldnt adding CO2 effect the direct correlation between pH and KH? I dont quite understand what you mean...
Sumpin'fishy
12-21-2002, 11:05 PM
I'd hit the plants forum for more detail on CO2. I understand it, but to explain it takes a while. Richer or Plantbrain would do a great job of explaining or pointing you to a related thread. Others will give some good insight too! I can tell you that pH, KH, and CO2 will all affect each other. If you mess with one, the others will change too!
Richer
12-21-2002, 11:30 PM
CO2 injection doesn't affect KH in anyway, it only affects pH. When injecting CO2 into a fish tank, a small percentage of CO2 associates with H2O (the water) and becomes carbonic acid. That is what lowers the pH. We can determine CO2 concentrations by measuring KH and pH because there is a predicable trend between the 3 variables.
HTH
-Richer
Sumpin'fishy
12-21-2002, 11:46 PM
Yea, I just re-read what I said, and I was pretty unclear with what I was saying. What I meant was they form a relationship with each other, and to change either of the other two will change pH, although the amount of KH will help stabilize this change. For example: add CO2= lower pH, Raise KH= higher pH.
Due to the depth one can go into in this topic, I have left it to the pros to instruct others. I humbly bow out:)
More than you want to know:
http://www.tomgriffin.com/aquasource/hardwater.shtml