GH and KH - Should I care?
- Thread starter aquanewb
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GH and KH are two measures of hardness in your water. In an unplanted tank the two times it becomes really important is if you keep African Cichlids or want to breed fish. In the case of Africans you want to keep the values high. In the other case some fish are only able to spawn successfully if the hardness is kept in a certain range.
In a planted tank (like yours) the values are important to help determine the kinds of plants you can keep. Most plants do not do well in hard water. In addition if you ever want to supplement with CO2 you'll need to know the values because it can affect your PH.
In a planted tank (like yours) the values are important to help determine the kinds of plants you can keep. Most plants do not do well in hard water. In addition if you ever want to supplement with CO2 you'll need to know the values because it can affect your PH.
Well, seeing as how you have a planted tank, yes, you should care. KH will help you determine how much CO2 is in your tank. I believe (though I may be remembering incorrectly) that gH helps in figuring out things like buffering capacity. Someone correct me if I am wrong, please.
Read through this thread...
http://www.aquariacentral.com/forums/showthread.php?t=35281
KH/carbonate hardness/alkalinity and buffering capacity - determines stability of pH.
GH/general hardness/total sum of all dissolved solids/but test kits generally deal with just calcium and magnesium concentrations.
Most plants do very well in water of 3-5dKH and 6-12dGH.
http://www.aquariacentral.com/forums/showthread.php?t=35281
KH/carbonate hardness/alkalinity and buffering capacity - determines stability of pH.
GH/general hardness/total sum of all dissolved solids/but test kits generally deal with just calcium and magnesium concentrations.
Most plants do very well in water of 3-5dKH and 6-12dGH.
GH and KH are important in the sense that they both relate to PH. For example hard water (high GH) tends to have a high PH as well as a high KH. Because of the high KH in hard water it makes it more difficult to lower the PH. I would say it's good to know all three of these especially about your tap water.
GH does not influence pH. GH is not total dissolved solids (TDS) at all, it is calcium and magnesium ions.
KH does control pH in unadulterated water.
KH does control pH in unadulterated water.
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Here is another article I found that explains 'hardness' fairly well.
http://www.aquariumpharm.com/articles/gh-kh.asp
..and
http://www.aquariumpharm.com/articles/gh-kh.asp
..and
I stand corrected.