Cool, thanks for the link. I can't wait to see the pics with the clams in it. What kind of check valve are you going to install?
I've personally gone with siphon break holes on all my returns because I've read lots of horror stories about check valves. If someone's come up with a better one that would be really great info to have. I think this is a very cool project. I never would have thought of it. It's almost like a reef fountain.
