Its a 150 gallon with a built in overflow which flows into a 40 gallon fuge for filtration. There is a NaturalWave pump system to give variations in flow around the tank and for lighting there are 2 400 watt 14k hamiltons. I can't remember the size of the pump in the fuge, but it has quite a bit of flow. Liverock...can't remeber the exact lbs, but quite a lot of it!
As for growth on the overflow box, the rocks were placed close to the coralline encrusted overflow, giving a good surface for growth. The zoas took care of the rest.