Originally Posted by acitydweller
I'd skip the calcium carbonate(cuttlebone) as it would raise KH as well as GH. Magnesium sulphate (MgSO4) or Epsom salt will raise GH without altering KH. Used in a ratio of 1:3 with CaSO4 (Calcium sulphate) or plaster of Paris. Use 1 part MgSO4 to 3 parts CaSO4 to make your own GH booster.
Expense isn't so much of an issue as effort and time because the cost of these materials would likely last longer than a $18 bottle of shirakura CA+.
Wow! That is mind blowing!
Plaster of Paris and Epsom salts!
What shrimp do you use this with? How long have you used it?