How much flow can a 1" drain take ?

[PatientZero]

I am working on rebuilding a 90 gallon acrylic tank and I noticed the drain bulkhead is only 1". Is there any guideline on how much flow a 1" drain can handle? I could put 1.25" before and after, but the bulkhead is the limiting factor. Thoughts?

[brandon0350]

Not sure if this helps, I have a varios 6 running full speed and I have a 1" drain. It is full siphon with and emergency overflow though

[LotsaFishies]

If under pressure, a 1” pipe can push up to ~1,400gph.

Under no / low pressure (like a drain) expect a max of 600-700gph.

The type of overflow you employ will make a small difference... a fully submerged “Herbie” style drain that is has 12”+ of water above it pushing down will handle more flow than a surface-level Durso-style drain, even if the same diameter pipe.

[LotsaFishies]

Also, assuming that you have the space in the overflow to do so, you can always just drill a larger diameter hole. Drill a hole for a 1.5” bulkhead if you have the space. I have done this before.. drilling a hole around a hole.

[PatientZero]

Thanks! Maybe drilling is a better option since I don't have a back up drain.

Lotsafishes: How hard is it to do with you area drilling around an existing hole? Does not having the pilot screw make it more difficult?

Brandon: I was considering a varios pump, how do you like yours?

[brandon0350]

Thanks! Maybe drilling is a better option since I don't have a back up drain.

Lotsafishes: How hard is it to do with you area drilling around an existing hole? Does not having the pilot screw make it more difficult?

Brandon: I was considering a varios pump, how do you like yours?

Second Varios 6 I've owned. Never had an issue and they are dead silent

[LotsaFishies]

It’s not “hard”... just requires finesse.

You drill it without using a pilot hole.. same way you would drill a glass tank, holding the drill and bit at an angle (very carefullly!!) and slowly sink it it in..