If they are up to the top of the water column, and you smell a bit from the water in the pond, I'd try to open up more with the pump. Next year try to have more area open. No issues here with 5% open water but you may need more.

What percentage of the pond surface area has open water now? (guesstimate on the size of the open hole is good enough for calculations)

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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).