Can you describe the external parasites? There might be a bunch of snails in there that you haven't noticed. I'd throw in 500 RES per surface acre.If you look at the record sized RES in Lake Havana, they are that big because of Quagga Mussels.

With the pond being that shallow, I suspect that there is a considerable amount of aquatic vegetation that might need some management. Not all of it, but if there is a considerable amount, then removing some will help the LMB hunt down the shiners easier.

It might not hurt to throw in 25-50 HSB to chow down on the GSH. If they HSB thrive in the pond, adding 25 - 50 per year and then harvesting that many per year starting in 3-4 years after stocking them might be helpful for the GSH population. .

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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).