Trying to figure out how to put in a nice fuge??


I have a 125 salt that I am setting back up from a move. Currently all I have are the fish (1 vlamenji, 1 red coris wrasse, 1 coral beauty, and 1 goby) which are safe in my 40 gallon that is already set up. My question is how to add a refugium to my setup. I have a sump that will be installed in the basement and that is where I would like to add my fuge. The sump is probably about 20 gallons, so I don't feel that the area that I could use for a fuge would be large enough. I have several 10 gallon tanks lying around that I could use, but just wondering how to plumb it mainly. I will have the overflow going into the sump and the return pump is directly connected to the sump by a bulkhead. Can someone give me an idea how to get this done?? Thanks in advance!!
Mine is a separate tank off of my basement sump. Sump has 3 chambers. 1st is from display. 2nd has skimmer in it. 3rd is return/top off section.

I have a Taam1700 (throttled back) in 2nd chamber. It feeds a 20gal off to the side with macro in it. The 20 fuge is drilled and has a 1 inch bulkhead in it and it sits up on some blocks. The fuge drains into the return section of my sump. I have a cheapo $10 39watt flourescent bulb in a clip on fixture from Home Depot. Thats about it.

The trick is to drill the fuge so that it can drain back into sump. Other than that, nothing to it.