This is the same design as the ones over at Robertsdale Feed. The biggest squash plant I've ever seen was growing in it last time I was there. It was climbing up the building and going all over the place. I think you are going to have an excellent set up going...
Im thinking 3 beds per side,with the fish tank feeding 3 at a time on a timer,but it might be too much for greenhouse space wise.Thinking 2 separate air pumps,each working an air pump for water pumping,staggering the times they run,1 pump feeds 3 beds each.Dont know,might have 2 tanks and 4 beds,just have to see how space works out?
Plus have to figure out how to have one side drained while other fills.Then there is the water sump issue to address too.Barrels maybe,I have no idea yet.Havent researched that deep enough yet.
Mrs wants some space other than aqua too.
BTW,bud with hydro,went to check him out,doing really well,he says trick is keeping water super oxygenated with a pump.He has all kinds in various stages of experimentation,I was shocked how healthy it all is doing.He too has a huge squash and a huge pumpkin growing out of a 10 gallon water tank with hydro nutrients.
Here's tristans pic showing three beds
http://ibcofaquaponics.com/systems/tristrin/Oh,and the issue with the IBC not being UV protected has been solved,they will get Black Krylon Fusion paint jobs.