I am about to purchase a 180 gal. tank. I would love some ideas on the best way to have it drilled for a closed loop. I can have it configured anyway I want, but would like to use only two pumps. I may wind up using three, but prefer two. I plan on keeping SPS with a DSB. I will have a refugium, along with a calcium reactor, once I buy one, and probably a uv sterilizer. Any help would be appreciated.