Is it this one?
http://shop.aquatraders.com/Hang-On-...in-p/43017.htm That looks pretty cool.
Did you buy a
powerhead for it? If not, you need a powerhead to pump the water into the skimmer/refugium. What are you planning on putting in the middle compartment? Put in any rocks, macro algae (need a light too), sand, etc in the middle compartment then fill with water and plug it in with dry hands. Usually takes a couple of days or weeks to start getting good stinky dark stuff in the skimmer collection cup.
I ran a
DIY hang-on aquaclear fuge - see the
refugium article