3/4" or 1" return - help please

Regulator23

New member
thank you. I have 2 reef tanks (125G and 110G) that I am about to consolidate my fish and corals into a new acrylic 180. The 180 is peninsula style (viewed from 3 sides) with a single overflow box on one end. In the overflow box, there are two drain holes that will accommodate 1 1/2" PVC (I'll use 1 for drain and one for emergency) and a single return hole which will accommodate a 3/4" PVC. Here's where I need help.

Do you think it would be advisable to drill the return hole larger to accommodate 1" PVC? Both of my other tanks use 3/4" but I don't have nearly as strong of a pump on them (my new pump will push 4,100GPH at full power).

Not sure if it makes a difference, but I'm also going to run 2 MP40's from the same end of the tank. Flow shouldn't be an issue.

Anyway, that's one question/dilemma.
 
Your return hole size and piping used should be suitable for the pump being used and to not create a restriction..

Typically that would be the same size as the outlet of the pump or greater..

I highly doubt your 4100GPH pump has such a tiny 3/4" outlet..
And NO WAY are you going to get 4100GPH through 3/4" or even 1" really.

oh and FYI.. Typically for a 180G tank having return pump flowrate of up to 1800GPH after head loss.. (typically recommended to have 3 to 10x display tank size) is suitable..
4100GPH is massive overkill unless your sump is in your basement or 10+feet below the display tank
 
If you are going to use loc-line on the inside of your tank on the return, might as well stay with the 3/4" bulkhead. As far as I know ( or could find) loc-line doesn't come in 1"
 
Got it. I have a smaller pump I think I'll use instead (I was just thinking bigger is better!!). I will have a manifold running off it, but that won't draw much flow at all. Thank you.
 
MP40 will only make it half way, go with 1.5" Everything and use the big pump. If you want quiet go with DC.


Sent from my iPhone using Tapatalk
 
Other than the ability to fit bulkheads (don't forget the flange size and space to swing a wrench), larger pipes are never worse. If you are using loc-line you can always bring up a large pipe, split, then have multiple loc-line outlets.
 
4100 GPH is a lot of flow and way more then you need. For that much flow you really want 1.5” tubing. I doubt you overflow will be able to handle 4100 gph. It is also very possible your sump will not either. It costs a lot in electricity to pump that much water up 6’ or so with no real benefit. Like uncle said 1800 GPH is plenty.
 
Back
Top