I don't have a good answer for you. I wouldn't be concerned if I saw a few fish per month die. I might have that in my pond, but with the few turtles in there I don't see many. I figure a few fish die, what part of the total population is that? If it's under 1/2 percent, it's acceptable.

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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).