Ditto what Bill said about the nutrients. I'm seeing more cases of Blue Green algae this year than in previous years.

As Nate will tell you, the key to having good sized predators in a pond is the forage base. Both in terms of numbers of forage fish and having them the correct size for the predators to eat and not expend too much energy catching them.

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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).