Overflow fluctuating

[Reefnewb]

Can anyone tell me why my overflow level fluctuates when my water level in the return section goes down? Herbie drain, jebao 10000 return pump.

 

[S-t-r-e-t-c-h]

Is the sump end of your piping submerged? If not, you can get air introduced from the bottom, which will make the flow of the siphon fluctuate.

Give a little more info on how it's fluctuating though, as it could be the valve needs adjusting, or some other reason. The link below is very helpful in the meantime:

http://gmacreef.com/herbie-overflow-reef-tank-plumbing-method-basics/

 

[Reefnewb]

Is the sump end of your piping submerged? If not, you can get air introduced from the bottom, which will make the flow of the siphon fluctuate.

Give a little more info on how it's fluctuating though, as it could be the valve needs adjusting, or some other reason. The link below is very helpful in the meantime:

http://gmacreef.com/herbie-overflow-reef-tank-plumbing-method-basics/

When the water level in the return section goes down due to water evaporating the water level in the overflow goes down too, and causes it to become loud and annoying. When i fill the sump back up to normal operating level the overflow will go back to normal on its own. Are you asking if my return pipes from the herbie drain are submerged? If so then yes they’re below the water about 1.5” as recommended.

Iv never had this problem and i setup this herbie like i did in my past 3 tanks. 3/4 pvc return, 1” full siphon with gate valve, and a 1” emergency drain. The return is a DC pump so i do not have a valve on the return.