River, You could also set up an RAS system.

Here's a link that talks about them.

Recirculating Aquaculture System (RAS) link

If you do a google site search (go to google and type in (or copy and paste) the following phrase:

ras site:pondboss.com

you will get a bunch of good links.

JHAP
~~~~~~~~~~
"My mind is a raging torrent, flooded with rivulets of thought cascading into a waterfall of creative alternatives."
...Hedley Lamarr (that's Hedley not Hedy)