Kru:

I'm sure the experts will chime in here in a short bit, but I wouldn't fill in the pond any. I believe the shallower pond will be more prone to winterkill.

If you are going to renovate the pond, now is the time to do it while your fish population is at it's lowest.

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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).