Firstly I suggest that you verify those depths of 15-20ft and prove that the depth is not 7-8ft. The shallower the more prone to winterkill. The sugggestion of using 3/4" pipe to the water line was good. In winter IMO you do not need to run the aerator 24/7, IF the frozen area above the diffuser has clear ice and no snow, due to recent refreezing. Restart aerator, reopen the boil zone area when new snow cover appears. However on-off aeration in winter runs the big risk of the check valve not operating properly at the diffuser and allowing water to enter the entire underwater airline. This allows a plug to freeze at the water line thus blocking airflow. To reduce the chance of a frozen plug forming, clean diffuser in fall before ice cover. Aerator should have a pressure relief valve on the manifold to protect the compressor from over pressurizing due to airline plug. Or just run 24/7 if you have the cash to expend for aerator electricity.

For winter operation I would operate one or both diffusers each pulled close together into shallower water 4-6ft. Aeration at this depth can still provide some warmer water refuge at the other end of the pond. Fish will seek their comfort zone. Removng some snow cover at the opposite end of the pond from the aerator would be very beneficial for helping oxygenate the areas at the far end of the pond. Although horizontal aeration currents travel pretty far in a small pond.

If you stock YP-SMB, this fishery combo can be very easily converted to a LMB-BG combo by just adding a few larger BG-LMB. They will do all the rest for almost complete conversion in 3-5 yrs. When you start the restocking process keep us advised of the progress.

Last edited by Bill Cody; 05/04/11 02:33 PM.
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