onethunder,
Here are a few pictures of the space below my 75. Don't mind the mess. I have a couple little ones, so all my stuff goes in the stand or it grows legs and disappears.
Here is a picture of the Wetdry. It has two inlets, but only one is hooked up.
It is pretty busy. I have two return pumps in it. A Mag 7 to drive my DIY skimmer, and a rio 800 to feed my cheap refugium.
Here is my cheap refugium. It is made of a clear 10 gallon tote. There is a hole drilled in the left front side for the return to the wetdry. I am running 1 inch pvc for the return.
The tote sticks out the back of the stand a couple inches, and is too short. I made a very simple stand out of 1/2" plywood and 2x4's to raise it higher than the wetdry. I pump water into the back using the rio pump, and it flows out the front to the wetdry. This setup can't handle much more than 100-150 gpm, but you really want a slow flow for maximum effectiveness. Here is a picture of everything from the fron of the stand.
For me, I tried to find as large a container as possible that would fit in the stand, but still have clearance for the light. I am just using a cheap shop light with a sunbulb from lights of america. Don't have a good picture of that yet.
Sorry if that is a whole lot of info you didn't want. Just trying to be helpful. BTW...With a slow flow, I have a lot of cyano growing in the fuge, but it hasn't shown up in the display.
Fred