120g plumbing with Modular Marine overflow

[Hexamoo]

Hey all,

I’m currently setting up a 48x24x24 tank and have a 1200gph modular marine overflow box. This comes with 3 x 3/4” bulkheads.
Is 3/4” pipe work going to be big enough for this size tank? I have a reef octopus varios 4 pump that I’m planning on using for the return, so flow rate is adjustable on that. But I’ve dry fit plumbed the overflow yesterday and it’s just left me wondering if the pipework is big enough, it looks a little narrow to me.

I’ve done the box plumbing as a bean animal (I think? How I interpreted it anyway) I just need to drill the hole in the cap on the Tee but not sure what diameter hole it needs?

I bought this size box based on their site stating it’s suitable for tanks up to 150g so I’m hoping it is enough, as the tank is now drilled to this size overflow box. If it isn’t I could see if I could increase the bulkheads in the box to 1”

 

[Hexamoo]

I’ve just had another idea if the 3/4” plumbing isn’t big enough, I could maybe use the 1” holes I’ve drilled for the overflow as the returns, sell this overflow box on and purchase a bigger version?

 

[KStatefan]

How much flow are you wanting?

 

[Hexamoo]

If what I’ve read is the correct flow, (3-5x) probably around 5-600gph

 

[KStatefan]

A 3/4" full siphon will flow that.

 

[Hexamoo]

Oh cool thank you, I’ll carry on with gluing it all up then.