Thanks Ande for the 5 posts you directed me (to) for my question. I just skimmed them and found some valuable inromation. I have to read more carefully to find references to variable output pumps; didn't see any from skimming.
Another matter: is there such a thing as dictionary of aquaponics acronyms?
I just joined the forum. I am a longtime traditional grower of plants and animals. After reading a couple of books then thinking about setting an aquaponic set up, I imagined that it would be much easier if there were variable output pumps. No doubt by now many others have come up with that brilliant idea. so I put the key words: "variable output pumps" in half a dozen search b oxes so far and .... without a doubt, someone here can start me in the right dirrection. Thanks CalmRon