Sounds like you might have inadvertently created a super saturated DO environment where DO can actually exceed 20 ppm. IIRC that can lead to gas bubble disease for our finned friends. Can be as deadly as low DO. Seems to me DonoBBD reported something along that line a year or so ago in his pond in Canada.

Last edited by Bill D.; 12/20/17 11:01 PM.
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