Problem with overflow shaft

[Joko]

Hello friends
I have a little problem and the experienced aquarists here can certainly help me.
I have an aquarium of 600 liters and my filter tank is in the basement. The way from the aquarium to the filter tank is about 5 meters. The piping from the drainage water is 40mm. I have the following problem:
My water level in the overflow shaft remains constant for a few days, and then it suddenly drops a few centimeters in the overflow shaft, although I have not changed anything.
I have a ball valve downstairs in the basement with which I dammed the water. Can any of you tell me why my water level does not stay constant in the overflow shaft?
Thanks very much

 

[blaxsun]

Do you have a gate valve to regulate flow?

 

[Joko]

Yes, down in the basement by the filter basin

 

[homer1475]

Return pump?

I would guess it's the return pump not putting out the same amount of flow 24/7.

Is that a durso, or herbie setup?

 

[Joko]

Return pump?

I would guess it's the return pump not putting out the same amount of flow 24/7.

Is that a durso, or herbie setup?

Herbie Setup
The pump is a Jebao DCP 20000, I had it tested and it works fine and it's a new pump.

 

[Joko]

I even swapped the pump with a Deltec EFlow 10 24V, and the problem remains the same

 

[homer1475]

You could try lowering the main siphon line a bit. Might help.

FYI jebao pumps are known to spit and sputter sometimes, and not have the same amount of "push" 24/7.

 

[homer1475]

How do you have the herbie setup? Looks to me like the emergency is way too high to accommodate the small fluctuations in flow.

Looking at the picture again, I'm almost certain the main siphon line is too high.

 

[Joko]

You could try lowering the main siphon line a bit. Might help.

FYI jebao pumps are known to spit and sputter sometimes, and not have the same amount of "push" 24/7.

Yes, I will try to set the main siphon lower. Yes, I have already read about the Jebao pump, but as I said, I also tried a Deltec pump and I have the same problem

 

[homer1475]

The strainer may be sucking air, causing you to loose siphon. So the water level goes up, then when the full siphon starts again, it lowers the level.

 

[Joko]

How do you have the herbie setup? Looks to me like the emergency is way too high to accommodate the small fluctuations in flow.

Looking at the picture again, I'm almost certain the main siphon line is too high.

The main siphon line is completely below the water level and the emergency overflow is 1 cm above the water

 

[Joko]

The strainer may be sucking air, causing you to loose siphon. So the water level goes up, then when the full siphon starts again, it lowers the level.

Thanks for your tips

I will try to lower the main siphon and hope that it will work then. I'm really desperate with it

 

[homer1475]

Have a read through this:

Herbie Overflow Plumbing Guide for Quiet Reef Aquariums - gmacreef

The Herbie method can quiet down your aquarium drain and eliminate microbubbles. The guide includes helpful diagrams and explains each component.

gmacreef.com

Explains exactly what your issue is, and why you have the fluctuations in the overflow.

Basically your full siphon line is too high.

 

[Joko]

Have a read through this:

Herbie Overflow Plumbing Guide for Quiet Reef Aquariums - gmacreef

The Herbie method can quiet down your aquarium drain and eliminate microbubbles. The guide includes helpful diagrams and explains each component.

gmacreef.com

Explains exactly what your issue is, and why you have the fluctuations in the overflow.

Basically your full siphon line is too high.

Many thanks for the help

 

[homer1475]

No problem. Just come back and tell us if that fixed the issue.

 

[Joko]

No problem. Just come back and tell us if that fixed the issue.

Of course I do

 

[Joko]

Hello sea water friends,
As recommended by you, I rebuilt my overflow shaft as suggested to me, but unfortunately without success. That means my water level in the shaft remains constant for a few days and then it falls a few centimeters in the shaft. I don't know what to do and I'm slowly despairing of it
Would you be very grateful if someone could help me

Thanks very much

 

[homer1475]

A herbie drain is not a set and forget like a bean animal. There is always small fluctuations in the water level. If you leave a trickle down the emergency, the water level should remain mostly constant, but you will notice some small fluctuations(sometimes it goes up and water goes down the emergency, sometimes it goes down a little bit). If it goes down a small bit, it should catch back up.

I currently run a herbie drain, and there is always small fluctuation that I have to constantly fiddle with the gate valve on the drain line. It's just the way it is with a herbie.

 

[fushi]

Hello sea water friends,
As recommended by you, I rebuilt my overflow shaft as suggested to me, but unfortunately without success. That means my water level in the shaft remains constant for a few days and then it falls a few centimeters in the shaft. I don't know what to do and I'm slowly despairing of it
Would you be very grateful if someone could help me

Thanks very much

How do you top off your tank, with an auto top off?

My tank does something similar. When my ATO is off or not working the water level of both my sump and overflow box go down with evaporation.

I believe this is due to the change in pressure in the pump output due to the amount of water above the pump intake causing the pump to slightly decrease its output at the tank level.

The simple fix is to get a good ATO with the float switch in return pump chamber.

I should also mention I find it best to adjust the main drain valve so the water in the overflow sits exactly at the top the the emergency drain or slightly trickles into it. You should be able to see it drop a centimeter below the emergency overflow with evaporation and pop back up a centimeter after you ATO pumps water in.

 

[Joko]

Hello
Unfortunately, I can't get my problem with the water level in the overflow shaft under control. I just don't understand why my water level in the overflow shaft drops by a few cm after a few days or even after a week. I have a ball valve in the basement and turn it Then again and again a little when the water level in the overflow shaft sinks, but it happens again and again that the water level sinks. And since there is more water in the technical basin, my water level rises and then disrupts the function of my skimmer. Nobody really knows why the water level in the shaft is dropping? Should the drain pipe perhaps suck in air and thereby the water level drop? I don't know what else to try. Maybe someone of you can help me.
thanks