Whats happening with my overflow?

[johnm92172]

I have a 110 gallon 3/4 cylinder tank by Aquavim. The tank is 3 feet high, stand is about 3 feet as well. the overflow which is at the back has a 1.5" drain pipe, and the sump has a 1" pipe to return the water from the sump. I have a 1" to 3/4" reducer on this pipe. Sump pump is a ReefOctopus Various 6. When I start the pump it fills the overflow pretty high, but then all at once the drain pipe takes it all down almost all at once until it fills up again and then does it again over and over. When I lower the flow from the pump, it evens out, and works normally. Question is, why does this happen? Is it that the pump is too much for the tank? Or is it that 1" to 3/4" adapter at the return pump?

 

[Vinny Kreyling]

It has to do with the type of overflow, Durso or Herbie?
Durso's do no like flow & run best with low flow as you have discovered.
Herbies can handle more.
As to why -- the higher water level creates a siphon which flows water fast thereby emptying the box of water till the siphon breaks starting all over again.

 

[jeffchapok]

I made a baffle out of PVC and a drinking straw to quiet mine down, then added some foam around it to further muffle the noise.

Sent from my moto g(6) using Tapatalk

 

[johnm92172]

It has to do with the type of overflow, Durso or Herbie?
Durso's do no like flow & run best with low flow as you have discovered.
Herbies can handle more.
As to why -- the higher water level creates a siphon which flows water fast thereby emptying the box of water till the siphon breaks starting all over again.

Yea it's a durso. Well the octo is turned all the way up before the last light and it's running ok but just can't use that max setting.

 

[moondoggy4]

You have more water going through a pipe with not enough air. Causes a flushing.

 

[johnm92172]

You have more water going through a pipe with not enough air. Causes a flushing.

Any way to fix that?

 

[OneReef]

You can try drilling a larger hole in the top of the Durso cap to allow more airflow

 

[Entropy]

You can also drill more holes in Durso cap instead of making the single hole bigger. That way if you go too far you can just plug the last hole drilled. PVC caps are fairly cheap, so you could also have a couple spares.