240 gallon planning

[bmcq]

I am planning my new 240g and need to get some clarification on a few details before I order my tank. I want to have 4 - 3/4" returns in the back of the tank 6" down from the top. Hopefully I will be able to direct my flow from these through my live rock So everything will be hidden. Could this be a problem? I also plan to use a 20 gallon long sump as a refrugium that will be located to the side and above the tank so it can be gravity fed back to the main tank. I plan to run a 1/2" line off of one of my return pumps with a valve to regulate flow. Will a 1/2" line provide enough flow so that pods, etc. will be washed into main display? I also plan to use an OM-4 on a closed loop with a separate pump. My whole idea is to have no evidence of plumbing or pumps inside the main tank. It's dimensions will be 96x24x25. I am also wondering what the current thinking is on DSB. I have also seen references to RDSB ... which means what? All comments and suggestions will be greatly appreciated.

[bmcq]

bump!