Over flow shaft and water level

[Joko]

Hello dear seawater friends

I'm getting back here because I still don't have a solution to my problem with the water level in the overflow shaft. my filter tank is in the basement,and the piping is about 4. 5 meters long. outlet pipe is 40mm and inlet pipe 32mm. I set the water level in the overflow shaft optimally,and it stays set that way for +/- 2 weeks. but then the water level in the overflow shaft slowly drops during two/three days,and then it rises in the filter tank in the basement,and at the top of the tank it starts to ripple. but why is my water level dropping in the overflow shaft?
- Do pumps have fluctuations?
-Should I perhaps throttle my pump then?
I just don't know what to do anymore and would be really happy if someone could give me some advice.

Thank you

 

[blaxsun]

Do you have a gate valve on the overflow plumbing?

 

[Joko]

Do you have a gate valve on the overflow plumbing?

I have a shut off valve on the overflow at the bottom of the sump and a shut off valve on the pump

 

[reeferslav]

Wich kind of retrun pump do you use? I have heard that cheap pumps have problems maintaining a constant flow. Can you show pictures of your entire sump setup and return your pipe?

 

[Joko]

Wich kind of retrun pump do you use? I have heard that cheap pumps have problems maintaining a constant flow. Can you show pictures of your entire sump setup and return your pipe?

I have the Jebao DCP 20000, and before that I had the Deltec e-Flow 10 and it was the same problem with the water level

 

[reeferslav]

Maybe you just haven't found the correct position for your valve yet. So your drain is bigger than your return volume. What were your attempts to fix the problem so far?

Maybe the big amout of the bio filter affects the flow to yout pump chamber. Did you monitor the salinity over this period?

 

[Joko]

Maybe you just haven't found the correct position for your valve yet. So your drain is bigger than your return volume. What were your attempts to fix the problem so far?

Maybe the big amout of the bio filter affects the flow to yout pump chamber. Did you monitor the salinity over this period?

I measured the salt content and it's ok. The valve is probably set well, because I've adjusted it several times and it's almost at the maximum. I tried to make a small hole in my drain pipe because of the pressure or air, but that too didn't help

 

[Joko]

Hi Is there no one here in the forum who has his filter in the basement and can help me with my problem? Thanks

 

[Joko]

Can someone tell me whether my drain pipe in the filter tank has to be in the water or whether the pipe should be above the water level because of the air?

 

[RedoubtReef]

Have you tried raising the water level so that you get a trickle down the emergency drain? A number of folks say this alleviates the issue with having to adjust the Herbie style overflow.
I've always run mine with the end of the primary drain below the waterline where it comes into the sump.

 

[Joko]

Have you tried raising the water level so that you get a trickle down the emergency drain? A number of folks say this alleviates the issue with having to adjust the Herbie style overflow.
I've always run mine with the end of the primary drain below the waterline where it comes into the sump.

Yes, I've tried that too, and even always adjust it so that a trickle of water runs through the emergency overflow, but without success. My drain pipe is also under the water in the filter basin. Should I throttle the pump with a shut-off valve, so that I might be able to stabilize fluctuations in the pump.'I don't know, I just don't know what to do anymore...

 

[RedoubtReef]

Boy, that's a tough one. If it were me, I'd start with the pump at max and the valve on the drain wide open. Make an adjustment to close it down and wait 10-15 minutes. Continue that until you get where you need to be. I've always had to do some adjustment on my Herbie for whatever reason. Also, try keeping the water level constant in the sump by topping off so that the return section doesn't get to low.

 

[TokenReefer]

In your picture with the arrows, is that were you want the water level to be? The drain pipe is way lower than that and the water level seems to be at the emergency pipe level. Wouldn't you want the water level to be at the drain pipe level and then rely on the emergency as backup? Sorry I'm confused but I don't mean to add to the confusion, just trying to better understand...

 

[RedoubtReef]

In your picture with the arrows, is that were you want the water level to be? The drain pipe is way lower than that and the water level seems to be at the emergency pipe level. Wouldn't you want the water level to be at the drain pipe level and then rely on the emergency as backup? Sorry I'm confused but I don't mean to add to the confusion, just trying to better understand...

With the Herbie, you run it at the level he shows in the picture. You want the water several inches above the main drain and trickling down or at the emergency drain.

 

[TokenReefer]

Ah ok I missed that, sorry

 

[TokenReefer]

When the water level drops in the box and raises in the sump what action corrects it? i.e. how do you get back to where you like it?

 

[RedoubtReef]

When the water level drops in the box and raises in the sump what action corrects it? i.e. how do you get back to where you like it?

you have to adjust the gate valve on the primary drain to set the level.

 

[TokenReefer]

So that's where the problem lies then, right? Just trying to help troubleshoot.. The corrective action is a big indicator sometimes...

 

[RedoubtReef]

So that's where the problem lies then, right? Just trying to help troubleshoot.. The corrective action is a big indicator sometimes...

sorta. after a few days or week+ you may need to adjust. Seems to be based on evap/sump level and I've always thought that air pressure changes can affect it as well. Don' t know if I'm making that up or I read it some where.

 

[TokenReefer]

Hmmm. The fact that water level in the sump is rising says its not leaving the sump at the proper rate.. may be onto something with the return pump. Have you ever noticed change of flow upstairs? Have a gate valve fully open on the return? Have another pump to try?