220g dual herbie I’m thinking. what size/ how many return lines should I run over the back

[reefman323]

Upgrading my 100g to this 225g. It has 2 overflows one in each corner. Each overflow has 2, 1.75” holes drilled. So if drilled for a 1” bulkhead or 3/4 sch 80 bulkhead. I think I decided on herbie drain.

1.Should I keep the full siphon and emergency at 1” bulkhead?

I didn't want to run pipes outside the tank but I feel like that will be best for returns. Do I keep return line at 1” or go down to 3/4 and split it to two returns at top of tank?

Any other opinions or options I’m willing to take

 

[lapin]

Since I’m a big fan of Sea Swirls I say 2 returns. Leave the plumbing at 1”

 

[ca1ore]

I never have seen much advantage to using Sch80 bulkheads frankly. Reef Octopus make a higher quality line of PVC Sch40 bulkheads which I use exclusively on my tank. You could certainly go to 3/4 on the siphons unless you are looking to run crazy turnover. Keep secondary/emergency at 1”. I never had an issue with an over the back return. If you use black PVC it’s not that noticeable. I see no particular reason for multiple returns unless you need them for in tank flow. Power heads accomplish that much better anyhow.