Water falling into overflow

[aceashburn]

This is a second hand tank setup so I’m trying to make some improvements. I raised the weir on the tank to raise the water level in the display to the trim. Now the water is falling 2 inches or so over the weir to the level of water in the overflow which is quite loud. The issue I have is I can not raise the drain pipe much (half an inch) because of a glass lid and the air vent. The only thing I can think of is to reduce durso air vent which current sticks up around 2 inches. Any other thoughts or issues?

 

[Midrats]

A strategically placed piece of foam will stop that waterfall sound.

 

[Chrille26]

If you increase the flowrate of your return pump, or close the valve on the drainpipe to the sump, you can make the water level in the overflow even out with the water level in the display or maybe I misunderstand your setup?

 

[aceashburn]

It’s a reef tank so I have a single drain and return. I understand I should never have a valve on a single drain?

 

[Midrats]

Yeah, leave it wide open if it's a Durso style set up. You could always change it to a Herbie and run a return line up the back of the tank. That's what I'd do.

 

[aceashburn]

I'm going to try the foam route before making too many changes. Would like to keep it with a cleaner look. Thanks!

 

[LeftFootedJedi]

Put a piece of tubing (I had an extra one from my skimmer) into the drain & leave about 1/2” above the top for air. No more gurgling or waterfall sounds.

Worked on my WB 90.3

 

[RocketEngineer]

An alternative to foam is something dangling inside the box that the water can “stick to” and flow smoothly into the lower level. I’ve seen mesh, an old filter sock, netting, as long as it’s safe to use in the tank and can be shaped can do the job.