Okay... I got the demo system on a trial run. One problem I am having is that I have some leaks... I've tried twice to fix the with aquarium cement, but still an issue, as there's an area of my grow bed that cracked. It's a fairly small leak though, and I think I can work with it. The bigger problem is that I can't get my bell to siphon. Not sure what I did wrong. Gotta fiddle around with it some more. Our 4H gardening clinic is less than a month away now, and I'm getting a little frazzled with the problems. So gotta put my thinking cap on. Tested the water I put in yesterday, just to see where our tap water levels are. High ph, but everything else seems fine. Haven't got the fish yet. I have the seeds and grow media, so once I get the kinks worked out of the grow bed, then I can add those.