Close Loop Head loss

[Chad]

Ok, for the plumbing guru's.

I forget.. Do you lose pressure / GPH in a closed loop system?

I want to make a pretty complicated closed loop with a series of outlets inside the tank. There will be a single bulkhead coming into the tank and then multiple T's, 90's, 45's etc.

Will the Reef Central head loss calculator give me the total GPH I will be left with or is there a different calculator I can use?

I am trying to achieve a 40x turn over rate in my 34gal cube. So I need to match my pump and this CL system pretty well.