Refugium help for Nano cube 12 gal dlx

[TriniReefer]

Hey im trying to decide which filtration stage i should take out to make the refugium in.Which one do you guys use?Right now in my second stage of filtration i have all bioballs to help cycle my tank.How did you guys set up your refugiums and what did you use?Pics of them please too?Thanks i really apreciate it.

 

[schnell76]

In the second chamber. I would remove those balls first though. There is a great DIY thread on nano-reef, its about 15 pages long and has some awesome ideas. Thats where I got my info.