"Stephen Henning" wrote in message
news
I have a spring fed, 18,000 gallon, 17'x47' pond that I would like to
add a solar-powered aerator to. Googling found several.


[snip]

Only 1 problem with a solar powered aerator. They don't work when the sun
goes down, which may seem like a duh! kind of response at first glance.
However consider that plants switch from photosynethsis to regular
respiration in the absense of sunlight, meaning they use oxygen instead of
create oxygen.