overflow and return planning for non-drilled tank

[OneArmedBandit]

I recently picked up a 145 gal aquarium (72 x 18 footprint) for an in-wall FOWLR project behind a future bar in my basement. It is not drilled and I need to figure out what direction to go in that department. I’m thinking about 2 drains into the sump (or a coast-to-coast overflow) and toying with the idea of a closed loop system to minimize or eliminate powerheads. So, here are the main questions…

Bulkheads for overflow… Should I use 1 ½” or 2” (would it be the same if I did the CTC?)

Bulkheads for CL… What size, where and how many? Is four in the back glass and one on each side too many or should I use that ball joint type tubing to direct flow out of less bulkheads for the CL? I’m looking for medium flow since it’s FOWLR (small tangs and butterflies)

There will be a 75 gal or so sump directly underneath the tank about 4 feet below where the overflows will be. I plan to have a nice skimmer and quality pump in there too. I appreciate any guidance you all can provide, I only want to do this once… -Steve

 

[james3370]

check out my build thread. i know its only a 29, but the concept can be scaled up to a bigger tank. the only hole i have in my tank is for my glass-holes.com overflow box. the closed loop input & returns & the sump return are all over the top requiring no bulkheads

 

[OneArmedBandit]

I was thinking about running the CL over the top too, your build thread is pushing me even further in that direction... -Steve