>Now I haven't kept my "butterflies" in 20 degrees KH so I don't know if they
>show as bright of a color as I'm seeing in 1/2 salt.
I think we have to be a little careful here when we discuss degrees and ppm
with water hardness.
Degrees DH (German) = 1 part Ca Oxide per 100,000 parts water = 17.9 ppm.
Clarks degree = 1 grain Ca carbonate per imperial gallon.
American degree = 1 grain Ca carbonate per 1,000,000 parts water.
PPM = parts Ca. carbonate per million parts water.
Adrian.
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Adrian R. Tappin
"Home of the Rainbowfish"
http://www.ecn.net.au/~atappin/home.htm
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