Larry, I only clean them once a year. If the diffusers were to start plugging up, you would see more pressure at the compressor, not less. You might need a rebuild kit.

I don't think you "need" to run the aeration system when the water temp is below the low 50's providing the pond stays ice free.

If you have a boat to get out to where the deepest diffuser is placed, after a month of not running, go out there and have someone turn on the system. Smell the air near the diffuser. If it smells like rotten eggs (hydrogen sulfide) when it is turned on, you need to run them at a more frequent interval. If the smell is there, you have to do the 15 min/30 min/60 min startup again.

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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).