"FBCS" wrote in message
...
But you didn't answer the second part of my question. If airation w/
airstone is necessary what size and type do I look for. They do not hang
at
the top, but they are in full sun most of the day and in only 18" of depth
until I can finish digging. They is a slight waterfall they love to play
in
and swim against the flow.
snip

I am not sure of the correct answer. I can tell you that I aerate my pond
with a 300gph pump that is pumping up about 2.3 feet of head, and just
empties on a rock that splashes back to the pond. I dunno if that helps. I
have 3000 gallons.

BV.