How long to run it all depends on the system, now much water it moves, and what the goals are. Diffuser placement is critical for us northern guys.

I consider there to be 2 aeration seasons, winter and summer. For me, winter starts when water temps at the surface hit the low 40's. I switch from the diffusers placed in the deepest part of the pond to diffusers placed from 1/3 to 1/2 the total pond depth. ( 20' deep pond would have winter diffusers placed between 7' to 10' deep) I like to place the diffuser so that it keeps the pond thawed within 2' of shore or less. That way if someone/something gets in the water, they/it won't have to try and crawl up on top of the ice to get out. You don't want to run the diffusers in the deepest part of the pond during the winter because the fish won't have a "warm water" refuge to go to.

Summer starts when the water temps are in the high 40's or warmer. If the water is in the 50's or higher, depending on the depth of the pond, I'll switch over the deepest diffusers in start-up mode when I turn off the shallow diffusers.

I normally run the diffusers 24/7.

If you add bacteria to the pond bottom to try and reduce muck build-up, I'd run them 24/7 for sure.

Not all ponds are the same, and there isn't (aren't?) any hard and fast rules. But, I'd rather err on the side of having too much O2 vs. too little..........


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