Welcome to the forum!

I think that with your eutrophic pond, the best long term fix would be drain, rework the dam to remove the trees, clean out all the muck, re-compact the pond basin and start new. Get a legal pad and start making notes. Write down your goals for the pond and start researching. The Fall is normally the driest time of the year, and that would give you time to get a renovation plan together.

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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).