I would perform several large water changes over the next few days with well aged/aerated SW
. It could hopefully be simple water quality issue (DOC
/pH) but there is the possibility of Vibrio or Uronema.
Are the feces white/pale/stringy or dark and solid?
Stop using chemical additives to fix tank chemistry issues if just pH related. Use water changes and be sure the tank is getting proper gas exchange. Chemical additives are a bandaid that usually cause more problems than they solve. Hard to maintain pH will more commonly be related to the way the tank is set up/room it's in than chemistry. If the alkalinity is between 2.0-3.0 mEq/l, it won't be a chemical issue for sure. If using pH fix's chemically, you can raise the alk
too far and actually crash the pH which can in turn cause acidosis if not corrected quickly enough.