When I setup the shallow reef I went overboard with the equipment since I know what happens. I went with an Octopus Extreme 200 (rated for 250 gallons or more, I can't remember), Mag 9.5 return which had to be dialed down, Finex 300 watt titanium heater, and I had a bunch of other equipment left over.
I came across a 54 gallon corner tank and new it would be a long shot but the measurements were just short of perfect. When I put the 54 up against my tank it was within 1/2" height was as my shallow reef and witihng a 1/2" from the wall.

At first I was going to run two different systems but figured I'd see if I could run two tanks in one system. After doing some quick math and planning I figured why not. Believe it or not the hardest part was hanging the light. It looks bad up there at first but you get over that quick, the cables I mean.

Once in place and the light was hung I tackled the part I knew would be the a pain...the plumbing....
The plumbing starts at the mag 9.5 and comes up to a T.
To the left it goes to a ball valve and then up to a check valve and into the shallow reef.
To the right it goes through a ball valve then to a T fitting. The down part of the T goes to the fuge in the sump and the right part of the T goes to a coupling and up to the 54 gallon.
The drain comes down from each tank and into a dual filter sock return.
The reason the plumbing was so hard is because when I was tuning the ball valves to get the tanks to run together any adjustment to one valve would effect the other tank. It took a day to get it right but its running perfect now.
(Picture of plumbing to come tomorrow)
Here are the final shots of the new shallow reef add-on.
First the shallow reef. (as you can see...it was full)

The corner

