I am not sure how much this would help if it has anything to do with fish but I was told by a biologist to put a few bails of hay or barley in the water where it was almost submerged because it acts as a filter. I have not tried it yet because I just finished my pond but plan to this week.

3/4 Acre South Georgia Pond, 1,500 BG/RES; LMB coming soon

Father, forgive them: for they know not what they do.

Most powerful words ever spoken.
(Jesus Christ in Luke 23:34)