Duel Overflow stand pipe height

[speedo2wet]

On my new set up 150Gallon reef, I have duel overflows. I was wondering if they should be the same height or should one be 1" taller than the other as a back up? I would think the kits would come the same height but makes sense to have one act as an emergency drain as well. The pipe is 1-1/4" diameter Dorso stand pipe. The returns of course are the same height.

THanks

[Palting]

My sump was designed with twin overflow intakes, to go with the dual overflows of the tank. So, obviously, I want to have the drain pipes equal height with equal drain flows.

You could raise one overflow pipe higher to serve only as an emergency drain. The problem then is you have stagnant water in that tall overflow. Not a good thing to have stagnant water anywhere. Also, your full flow will only go down one drain, making that one drain quite noisy.

I would suggest making both drains equal.

[MrClam]

Depends on the drain setup you intend. Durso's would be better off as two of equal height to reduce noise. Herbie could have one emergency and one running full syphon, but you would need to install a gate valve. Beananimal needs 3 drains so you would need to use return lines or drill. The point about stagnant water in the emergency drain is a valid concern though so if you went Herbie you would likely need to address that with a PH or something.

[Fizz71]

Overflows should be the same height for the reason Palting said. Now if you're talking about PIPE height of two pipes in the SAME overflow that's another story. If we're talking "teeth" height they need to be the same....stagnant water bad, backups good.