Help with MP40 settings and trouble with overflow waterfall noise

[nbd13]

Hi,

So I have a 150 gallon tank that’s going to be SPS dominated. I have 450 gph going through 2 3/4” bulkheads for returns.

I have 1 MP40 on the left and 2 MP40s on the right.

I have a synergy overflow 16” model.

I am having a hard time getting the overflow quite. I can get it dead silent without the MPs on. As soon as I turn them on, I get a wave going in the tank and this creates a fluctuating water level in the external box which causes issues with the noise.

What settings do people have their MPs on to get flow but not a wave?

This video is with the MP40s off:


This is with them on:


It’s the alternating level of water in the tank causing the issue. Need help with settings for this!

Thanks!

 

[justmee]

IMO, I would try to turn down the flow on your return pump to a level where the water is just a tad above your main drain pipe... but I could be wrong.

Goodluck!

 

[nbd13]

IMO, I would try to turn down the flow on your return pump to a level where the water is just a tad above your main drain pipe... but I could be wrong.

Goodluck!

450 gph is not that much for return pump flow...

I need help with MP40 settings.