Before you throw a bass species in there that you will have to manage, I'd try throwing in some HSB. They won't reproduce. If you can get some WE, I'd put them in there too.

If the HSB can't keep up with the sunfish, add more, and if that still doesn't work, then add the SMB.

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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).