55 gallon garage aquaponic system is now cycling water. 600W bulb on 4 ft sq of future tomato paradise. Still a few weeks from stocking, but the heavy lifting is finished. I'm using a flood and drain running off a powerhead feeding from the undergravel filter in the tank. Tank is lengthwise on glass bricks on concrete in a narrow closet (39") on the back of my garage. I recycled a shelf to accommodate the grow bed, and placed it about 8" above the top of the tank (It's just particle board on rails so I can pull it out when I need to get in there). I'm concerned about how much heat that HPS is going to create in the enclosed space (no fans attached to it yet). The closet is uninsulated and it's about 22-25 sq ft, with a 9' roof (towards the door, it's the high side of the structure). There's a doggy door I can use as an intake (the dog has never once been coaxed through it), but I'll probably need to put in an exhaust fan before I start running the light. I'm pleased it's finally up.
Craigslist can occasionally play out well (tank - free, light - cheap).