Typical water depth of a raft channel?

[Calvin Schmidt]

What kinds of depths are you all using? I was thinking to build an in-garage system that i should be able to run year long here(zone 5a) and was going to model it similar to the Sweet Water Organics systems.

I'm going to start with a 4'x8' footprint and was thinking to make the bottom 2-3 feet a fish tank, then have two tiers of rafts above(actually a half width tier, 2x8, directly above the fish tank so i have access to the fish, then a full 4x8 above that). Obviously this would be growing under lights so I need to make sure i have room defined for the raft itself, plus room for growth and the lights(likely flourescents, T8s)

 

[David Waite]

Calvin rafts are normally 12 deep. Using 2 in foam board and 1 in water line the depth of water in normally 8 plus inches give or take . Keep in mind your rafts need to have clean water filtered some how to thrive. I am using a gravel growbed see my pics if it helps.