Posted these in my tank build but this is probably appropriate as well.
Here's what I came up with the stand pipe and the loc-line for the return. There's a 1/16' hole in the end cap of the stand pipe. I read to start there and drill out larger if needed.
I have the loc-line directing the return down the back wall and then the second output coming back and pointed towards the left wall of the tank. For the time being I'm going to use 3 or 4 Maxi-Jet 1200s to stir things up. I plan on upgrading to a couple Koralia 750s.
Over all shot from behind with components in place. Drain tube is 1.5" and after the sump is in place will basically go straight down into the first chamber. Vinyl return line is just sitting there. It's 1"" ID vinyl tubing which will go right onto the Mag 9.5" output then to the barb fitting. I still need to find an adapter for my Mag 7 output so that I can hook up my 3/4" ID tube to that for the skimmer.