Starting over here's my design.

[TomTom]

I have a 72 Bow with canisters and over the back, Skimmer and reactor. Now I"m going to a 48" 120 gal. tank. I have been buying things to make change for a while. I'm using a 75gal. for the sump and a 29 gal. refugium tank. That nice but here what is different. I'm using a 1 1/2 abs black pipe that is 36" long with 3 - 6" X 1/8" slots. The bar will 90 down at each end through the bottom in the basement to two socks in the sump. Bio balls , bubble baffles to a Reffol pump 3400 gph.. Out of the pump with 2'' to a y where I can control the flow to refugium. A 2nd y to the skimmer and reactor. The refugium would return to the sump. The idea is I can control the flow to refugium and have a max return to the sump. The supply would be 3 - 3/4 in the back. 2 low at the ends and one in the middle. I have check valves for the 3 supply. I have ball valves and unions. I am a maintenance manager and my brother is a construction contractor. Most of my plumbing and stands are left overs. Everything but my display tank are extras. U Tube and pet store I would like some more advise. Tom

 

[Reefing Madness]

Sounds like a plan you have there. But AZDESERTRAT would tell you not to use any check valves as they are not reliable enough, and can fail and leave quite the mess.
Other than that, we need pics now!! :bigsmile: