Well we all heard about Special Kitty and that we should test it first to see if what and where we buy it, that it is ok to use in out tanks.
I bought mine at Walmart here in Lexington, KY.
Using a Nutrafin KH/GH test kit:
Tap water GH - 7 drops or 140ppm
Tap water KH - 4 drops or 40ppm
Water from unwashed kitty liter after it set for 3 days in a bucket:
GH - I stopped after 20 drops or 400ppm.
KH - 9 drops or 90ppm.
This just goes to show you that when the experts says to test something, test it. I am glad I did.
10 gallon hospital tank.
29 & 50 gallon - High Tech C02 enriched.
50 gallon Pond - Natural.