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I have been wondering, what does "kh" stand for? And how can i check, and change it and what is the best level?

http://www.thousandfootkrutch.com
http://www.hawknelson.com

kH is carbonate hardness or alkalinity (not to be confused with alkaline). The higher the number, the more stable and resistant to chemical change (pH, etc.) the water will tend to be. It can be measured in ppm (0 to 300) or in *dH (degrees Hardness). Check out the Chemistry section under FAQ's at this site or try the following link:

http://www.drhelm.com/aquarium/chemistry.html

Hi,
You can check the Carbonate Hardness (KH) with standard
test kits such as the Aquarium Pharmaceuticals,Inc.
Freshwater Master Test Kit. You can increase the KH
of a tank by adding common ordinary baking soda. Be sure
to use only the unscented version. Baking soda will only
affect the KH and not the General Hardness (GH) of a tank.
Generally, readings around a 3 to a 6 (50 - 100ppm)
are considered great for plants and fish. Some fish prefer
"harder" water and can go as high as 22 (400ppm).

With a planted tank and injected CO2, you would want a
KH of at least 3 to 6.

Frank


-->>> The Confidence of Amateurs, is the Envy of Professionals <<<--

With a planted tank and injected CO2, you would want a
KH of at least 3 to 6.

Frank does the CO2 cause both kH and pH to go down to those numbers without any other additives? Next it is the CO2 that keeps the water in those ranges right? Stopping CO2 will cause the pH to swing back up will it also cause the KH to go up as well?
I am still trying to figure out how the CO2 affects the kH and how to control it, I want to have a good handle on this before starting CO2 in my own tank. Also, if I am planning to upgrade the light to 2 wpg is it better to do this before adding CO2 or add CO2 after the upgrade?


"If you're afraid you'll make a mistake, you won't make anything."
-Family Circus

OK this is very helpful, so i can go to the store and just but a test kit?

http://www.thousandfootkrutch.com
http://www.hawknelson.com

OK this is very helpful, so i can go to the store and just but a test kit?

YUP!
The test kits for kh and gh are usually the same, there's the strip which gives a general idea of what the levels are, it's not very accurate, just ballparks what each is. The Hagen test kits are much more accurate (as are the Master Test kit, and others) you determine the level by adding the reagent 1 drop at a time until it reaches a certain colour, then multiply it by 20 and that gives you the ppm value I believe. I have used the strips from Jungle for an idea of what the kH and GH are in my tanks, the liquid test is by far superior though if you want to know more exactly what your water params are.

"If you're afraid you'll make a mistake, you won't make anything."
-Family Circus

I have the "quick dip" version of the GH and KH test as none of my local retailers seem to carry the more accurate test. I may mail order one soon for more accurate results. The quick dip test from Jungle usually runs about $10 and contains about 25 test strips.

Hi,
Essentially, when you add CO2 to the water it forms a
weak acid and will lower the pH of the water. The
Carbonate Hardness of the water will buffer that downward
trend. Generally speaking, in a planted tank with injected
CO2, you would want a KH around a 3 with a 6 max.

This is a good article that goes deeper:
http://www.csd.net/~cgadd/aqua/art_plant_co2chart.htm

Hope this helped...
Frank



-->>> The Confidence of Amateurs, is the Envy of Professionals <<<--