I would definitely put the compressor in the barn. Try to run the airline very slightly as a down ward grade to the pond. This allows water to drain out of the airline and not lay in a belly of the airline that can freeze during winter. Before buying the compressor make doubly sure to verify the water depth is 22ft by actual measure - with brick and a rope. Pond builders almost always have their final dig as 1-3 ft in error. I always suggest not to use rotary vane deeper than 18ft. I have installed rotary vane diffuser system with the bubber up off the bottom on some sort of stand so it sits 18ft deep. If you use a dual or twin head diffuser in Ohio you should usually need to only run the aerator 4-6 hrs per day. Two disks or tubes instead of just one diffuser with the twin head mounted together will move twice the amount of water per hr and shorten the run time to fully circulate the pond. A 3 head diffuser will shorten the run time to 2-3 hrs per day for one pond turnover.

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