Yes, gypsum does increase hardness. I can get it at the local TSC for a relatively decent price, but thru all my searching, I've yet to find any information on how much is needed. I can add a little at a time, but don't want to overdo it, as with most treatments, results are usually time delayed. Also need to know if I'd need to do anything else in conjunction with it, like you would with an alum treatment.

Last edited by Mike Whatley; 11/11/18 03:24 PM.
.10 surface acre pond, 10.5 foot deep. SW LA. The epitome of a mutt pond. BG, LMB, GSF, RES, BH, Warmouth, Longear Sunfish, Gambusia,Mud Minnows, Crappie, and now shiners!!...I subscribe!!