External Overflow

[fservillon]

Hi all. I have an external overflow box that uses U-tubes that I want to use to setup a sump under my tank. I've used internal overflow with Durso standpipes in the past, my question is, would the external overflow box make a lot of noise since the drains are just straight PVC pipes? Do I need to install Durso's on them to quiet them down? How safe are these thing? ANy help would be appreciated. Tried doing a search but not a premium member so no go. TIA.
Fernan

 

[kevensquint]

I have my DIY PVC over flow draining into my sump, and it does make alot of noise. I don't care because it is not in a quiet room, but it sounds like when you pull the plug in a bath tub. BTW, its 1" piping

 

[Kaiser Tang]

There are a few problems with external overflows. First, the noise. They are more noisey than internal overflows. You don't need a standpipe. Just thread some airline tubing down the drain tube. This will allow air to flow easily through the drain tube. It still be more noisey than the internals, but the air tube will help. Second, externals work off a siphon. If the siphon breaks (which can happen easily) then you tank will flood. Some people use a reverse air pump wich sucks air out of the siphon to make sure it doesn't break. Third, every time you stop your return pump, the siphon on the overflow will break. You have to restart the siphon each time you turn this pup off.

I used an overflow on my old 65 gal. for about a month and decided that it was too risky and too much of a pain.

 

[Amador]

I have 2 Amiracles and they make a ton of noise without the standpipes. The primary source of noise is water falling from the U-tube chamber to the chamber with the bulkhead in it. I am using Stockman standpipes and they work pretty well. It's not totally silent, but it's MUCH quieter than using no standpipe.

They are pretty safe, provided your return pump is powerful enough to keep bubbles from forming in the U-tube. If your pump (or flow) is underpowered you'll get a gradual accumulation of air bubbles in the tube which will eventually break the siphon and allow the return pump to overfill the display and send water everywhere.

However, if your pump is the right size, you will never lose siphon, even in the event of a power outage.

I turn off my return pump all the time and never lose siphon, because the Amiracles (and Lifereefs) have a chamber that keeps that end of the U-tube under water at all times.