JCO & davidstcldfl, I'm thinking of putting an aquarium filter on the end of the pipe entering the GB to collect the solids from the FT. Putting the end of the pipe deep under the hydroton with the filter so algae doesn't grow. What about adding worms? Will that help the problem with the solids in the GB? I'm thinking the fish solids will just turn into worm solids...

I thought 7" would be fine for Lettuce and other leafy greens. I know tomato might have issues but I could just put a tomato cage in the GB. I guess I just need to make sure the bottom of the cage doesn't poke thru the pond liner.