Basically you are looking for 1 bluegill in an area that is 10'x18'. What size BG did you stock?

So, you are saying that you have had absolutely no other fish in there for the past 12 years other than the gambusia? The O2 levels are minimal for the bluegills. What time of day did you take the O2 reading? What did you use to measure it?

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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).