Overflow 125g


Reefing newb
I am going to be making my 125g into a saltwater. I am going to be need to get an overflow for my tank and I was wondering what flow rate that is needed for 125g tank.

Overflow Box 1500 GPH

This is what I am looking at right now.

You want the flow through your sump to be 5x-10x the tanks water volume, so your looking at anywhere from 625 to 1250 gph. A 1500 gph overflow should work fine.
I have a 55g tank in my basement that's setup as my sump.
Water drains from the tank and dumps into the sump on the right side and is pumped back up into the tank thru an external pump on the left side.
Ive ben doing 30gl every 2 weeks on my 125gl. I have a PF800 eshops overflow on mine. works great, i could go for a better return pump in the future as my overflow can flow more than my return pump can, i think im getting ruffly 650GPH up from my return pump, i would like it to be more like 700 to 800. But so far so good.
In regards to the overflow mentioned in the first post, i know this post is a little late but i can comment on that particular overflow. Its the same one i am using on my 120 and it works great. Install was really easy with the supplied template. Hope this helps.