Inspired by Boxster's 180 in wall construction (looks great by the way), here are some photos of the 120 we just roughed in in our basement.
This is a fish only salt tank (moved our 75 into bigger quarters.) The stand is primarily built from doubled up 2x4's with a treated 2x4 base anchored to the floor w/ 4x3/8" concrete anchors (as are all of the downstairs wall bases.) We used moisture resistant 1/2" drywall with a plastic barrier between the drywall & studs to keep moisture out as much as possible. Lighting at this point is provided by 2 4ft shop lights w/ 160 watts (please keep in mind, this is a fish only.)
The overflow is rated @ 800gph (second to be added later) flowing into a 20 gal
sump. Return pump is a Lifeguard Quiet One. Additional filtration is provided by a Fluval 404. Skimmer is an Oceanic 6 driven by a magdrive 5 pump.
Alot of work remains, including running a cold water lead & drain (to be added when the washer leads & drain are relocated) and a dedicated circuit coming from the fuse box.
In the future, if we ever decide to convert this to a reef, there is plenty of room above for MH
& room below for a second sump/refugium.