I used 2 different sized hole saws to cut holes in the back of the hood and a dremmel to make the straight edge to fit over the flow tubes. The refugium is the smallest of the CPR fuges. I got it on sale from one of the web suppliers. I got swaped out the pump with something a bit smaller with a lower flow. It all fits together perfectly. You can see the cuts I made in this picture...
Hey, nice mods. Must say done like a pro. Did some but having the cube for almost a year , didn't think i needed all kinds of mods. Made a fuge in second chamber; the light 13w, comming through the back, i pealed off paint with razor blade, will show pics later my cam is shot lol. A question ,to have a fuge an skimmer so big, what do you keep in there? My bioload is taken care of only by the original skimmer made for the cube. That why i didn't do more mods. Don't get me wrong , your mods are great and i change my bioload or have more difficult critters to take care of , i will upgrade the rest, good job, looks great.