George1, that isn't anything that I haven't seen before. The route that you took to clear it up is great! If I would have found PB earlier, and known about Tilapia's penchant for eating FA, then I would have NOT put the 100# of Copper Sulphate in the pond that I did over the past few years. My only savior is that the water gets exchanged in the pond due to ground water saturation. I even had the well tested for any copper traces and that was negetative. 125 3"-4" Blues went in this Summer and the FA problem was minimized. I think I wouldn't have any problems at all if I put in 10#/ac!

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3/4 to 1 1/4 ac pond LMB, SMB, PS, BG, RES, CC, YP, Bardello BG, (RBT & Blue Tilapia - seasonal).