bcotton:
I don't know if it would be cost effective, or if your plumbing is set up in a way that it would work, but you might be able to find selenoid operated valves that you could hook up to a timer. Leave the pump running all the time, an open/close valves going to different beds to make the ebb and flow instead of turning the pump on and off. You could probably get away with using a smaller pump that way too.
While I am not doing any aquaponics, I find your thread very informative. I am reading and learning! Thanks.
