Loud waterfall from tank

[reeflink]

Then you need to get a longer pipe.
Edit: can't stop the waterfall splashing noise without stopping the waterfall.

It’s the height inside my overflow that is the problem. I can get longer pipe but I’m almost at the top of my overflow with the pipe

 

[Dburr1014]

It’s the height inside my overflow that is the problem. I can get longer pipe but I’m almost at the top of my overflow with the pipe

Looks like your 3rd pipe (emergency) is taller. How much distance between that pipe in the top of the Overflow?

 

[thatmanMIKEson]

It’s not in the sump or the back of the overflow but from the tank to the inner box slotted portion of the overflow

I had this on a small over flow not rated for what I was pushing thru it. But I took the dremmel, to make the weir teeth bigger to make less pressure flowing thru them which splashes around in the box.

 

[DCR]

This is a well known problem with the Eclipse overflows. The external box is set too low relative to the internal box. This was done to get it under any tank top trim, but it causes the waterfall you are experiencing. You can raise the secondary as has been suggested, but you are limited by the height of the external box. I am not sure you are doing anything wrong.

 

[newbie2014]

This is a well known problem with the Eclipse overflows. The external box is set too low relative to the internal box. This was done to get it under any tank top trim, but it causes the waterfall you are experiencing. You can raise the secondary as has been suggested, but you are limited by the height of the external box. I am not sure you are doing anything wrong.

Hmm, if that's the case, then would it be possible for the OP to elongate the weir holes to make them lower, and thus decrease the water fall height?

 

[DCR]

Hmm, if that's the case, then would it be possible for the OP to elongate the weir holes to make them lower, and thus decrease the water fall height?

Yes, the OP could do that to reduce the waterfall height, but he will likely also reduce the water level in the tank an equal amount. The level would likely be below the top rim (if he cares about that).

I have also thought about eliminating the external box and just use the two through hole bulkheads to attach the piping directly to correct this issue with these boxes. One would be the full siphon and the other would be a secondary overflow (change from a Bean Animal to a Herbie). You have to create the overflow height on the secondary with the external piping.

Otherwise I would ask Modular Marine or Exotic Marine to custom make an an overflow (using the Eclipse template for the through holes). Both of these build their external boxes so they extend over the top trim.

 

[Soren]

Yes, the OP could do that to reduce the waterfall height, but he will likely also reduce the water level in the tank an equal amount. The level would likely be below the top rim (if he cares about that).

I have also thought about eliminating the external box and just use the two through hole bulkheads to attach the piping directly to correct this issue with these boxes. One would be the full siphon and the other would be a secondary overflow (change from a Bean Animal to a Herbie). You have to create the overflow height on the secondary with the external piping.

Otherwise I would ask Modular Marine or Exotic Marine to custom make an an overflow (using the Eclipse template for the through holes). Both of these build their external boxes so they extend over the top trim.

I wondered if this might be caused by a difference in overflow manufacture. My Modular Marine overflows are nearly flush at the top between inside overflow box and outside overflow box which avoids the issue at hand and, as you mentioned, could be the issue with @reeflink 's overflow waterfall.

I still think best advice without changing to a different overflow is to raise the durso pipe U as much as possible to see if it helps.