Cary,
You mentioned that aerators shouldn't be placed below 35 feet because atmospheric air is mostly nitrogen. Oxygen in surface supplied air never exceeds 21% even if you're pumping to 50 feet. I would think the reason for the 35 foot depth limitation was because of the horsepower efficiency of pumping that much air to that depth. Is the effectiveness of aeration due more to the oxygen percentage of the gas or the ability of the gas to move deep waters towards the surface where they can naturally be aerated more efficiently?


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