Splitting Return Line

[VGT]

Just picked up a tank with 4 holes in the overflow (2 Larger, 2 Smaller). Will be using the two large holes for a Herbie drain, and the 2 smaller ones for returns. I think there are two basic ways to split the return line - using PVC I can Tee the return and then two 90 degree fittings up to the return bulkheads, and then 90s again at the top (lots of head pressure), or I can use flexible hoses from the returns through a true Y fitting, into the bulkheads and then 90 at the top.

The return pump I'm using is a bit larger than needed, so I can afford the head pressure if I go with the hard plumbing and multiple 90s. Any reason to go either way?

Here's some crude drawings of the planned overflow plumbing and return options:

 

[Potatohead]

If you don't have head pressure problems, it doesn't really matter.

 

[mcgyvr]

A "sanitary" Tee would be another option too and work "better" than elbows..

 

[jason2459]

I've ordered several true wye fittings from here
https://flexpvc.com

 

[Synden]

T's will work and the water will flow, but Y's are the best for flow by far.

For an example, Bill Wann, guy with a 10k gallon tank, recently did an experiment on some of his plumbing. He has two barracudas that were plumbed with Ts, and he replaced one of the Ts with a Y and now he gets 15 gpm more flow out of the pumps. That's 900 gph just from switching one t for a y.

That being said though, generally a return is specifically for feeding the sump and the various equipment items contained there in, and then return the cleaned water to the main tank.
Often times we want longer contact time in the sump, so reduced flow on the return is not much of a big deal. If this were a closed loop though you would be looking to maximize flow and reduce head loss so you would want flex tube, with ys, or angles, but no 90s