After much deliberation decided not to recirculate the Vertigros.
Lots of pros and cons to this, but it will be much simplier to set up the 60 or more stacks. I kept thinking of the extra work,expense w/ plumbing, uniseals etc needed and then someone mentioned might be extra alage growth at all the rt angles I was going to have on the system... main reason is to keep it as simple as possible.
A huge pro is that I can now use one pump, which will also save electricity.
One big con- no extra oxygenation from flowing thru verticals and probably little more water loss.
I'll have a float valve set up,was thinking in raft tank, but Cosmo suggested in the fish tank, makes sense, to automatically fill water back to level.
I'm hoping I will really only lose 3qts per stack of water most of the time and when really hot out 4 qts day per stack. Two local friends that use verticals hydroponically on a large scale(700 stacks and the other has 180) quoted this same amount of water loss.
The raft tanks will be on a recirculating system w/ the lowest fish tank draining into the outer two raft tanks, possibly at multiply entry points and maybe flowing over oyester shells, like I've seen in some pics of systems online.
I'm hoping to start a bit of plumbing the tanks together tomorrow, we are leaving this week for vacation, so not sure what I can get done, lots going on.
I checked out some pumps at Home Depot tonight. I'm still not sure which pump is best for my system.
I think Chris in Hawaii suggested 3 gal per min.(thanks). I saw a "Beckett"med size pond pump that is around 210 gph. Wasn't sure if this was way too small, but seems to fit that reccomendation. It's a pond pump so OK, for continuos flow. I want to make sure I don't have a huge amount of water flow out of tops into the verticals, but also need a little pressure to keep the 1/8" tubes coming off the overhead 1/2" poly tube from clogging.. The pump states it can go to 12', but not sure how accurate that is.