From what I've been reading this may be an unusual question.
I am a volunteer with an facility that is careing for some
non-releasable bird. Among these are 2 ducks. They have a
small(garden type) pond available to them, I'd estimate between 150
and 200 gallons. It is getting dirty quite fast and the pump/filter
we had just packed it in. The pump/filter we had was rated at 190 gph,
and was cleaned on a regular basis. Is the anyplace online, of from
your own knowledge to determine what we need to do to keep this pond
clean?