How can I safely add calcium to my 130 gal. Angelfish aquarium?
Cheapest, safest, and easiest is dry ferts, in this case calcium sulfate:
Calcium Sulfate | CaSO4 | 1lb
Nilocg also sells a wide variety of other ferts and a GH booster that contains calcium, magnesium, and potassium together.
Will the calcium sulfate make my water harder ?
It'll raise your general hardness (GH) but not carbonate hardness (KH)
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