Display Tank Water Level Slowly Rising - Return Chamber Remains Constant

[joe1133]

Hi Everyone! I've been into SW for about 4 years now, but I've only had All-In-One tanks. I recently set up a 60 gallon marineland cube with a sump system. I've been nervous about doing a sump system for a while, because it felt really complicated.

Here are my tank specifications: 60 gallon marineland cube with a corner overflow. Since I'm new to all of this, I'm not sure what the type of overflow is called, but I'll attach an example picture found online. I have a 20 gallon sump with about 15 gallons. My ATO reservoir is one chamber as part of the sump.

Here's my issue...I've been experiencing varying water levels in my display tank. Around 1/4 to 1/2 of an inch of variation.

Before turning the ATO on, I've made sure that my overflow rate is matching my return rate, and the water is staying consistent in my return pump chamber. As I've been trouble shooting with the ATO off, I've watched this for 30 minutes to an hour, with no variation...letting me know that the water level has stabilized. I then turn on the ATO with the sensors in the correct place and leave it alone. For hours, everything will work with no problem. I've been tape markers at all of my waterlines (the ATO chamber, the return pump chamber, and the display chamber). The ATO chamber is changing throughout the day, as I would expect, the return pump level staying consistent, but the display tank water level SLOWLY rises. When I woke up this morning it had risen about 1/8 of an inch from last night.

Please help! I'm not sure what is going on, and it's making me feel like a sump system just isn't for me. I go out of town a lot and can't worry about the water levels all the time. I just set the tank up last weekend, so I know everything is clean...etc. Any ideas?

 

[WVNed]

Do you have anything catching on your weir. The slotted portion at the top of your overflow. How much water flows through the weir in relation to your return pump size is what controls your tank level.

 

[ca1ore]

Hard to say. Pics of the installed overflow and sump would help. Could be variations in pump flow based on return chamber depth or durso misbehaving.

 

[joe1133]

Do you have anything catching on your weir. The slotted portion at the top of your overflow. How much water flows through the weir in relation to your return pump size is what controls your tank level.

Thanks for your response! Nothing is catching, so I have no idea. It is so frustrating. Tonight, I noticed that my skimmer is inconsistent - sometimes bubbles in the neck and other times no bubbles. Could this be affecting the variation in my display tank?

 

[sfin52]

Welcome to r2r. Skim vs no skim should have zero effect.

 

[joe1133]

Hard to say. Pics of the installed overflow and sump would help. Could be variations in pump flow based on return chamber depth or durso misbehaving.

Here are some pictures. As you can see, I have tape marking the water levels, and if you look at the glass, you can see how high the waterline has gotten. I turned off the skimmer last night, because I noticed that sometimes there were bubbles in the neck and other times you couldn't see any bubbles, and it was affecting the water level in the return chamber...but I still don't understand why anything is affecting the water level in the display tank.

It feels almost impossible to have an ATO running right now, so I've just turned it off.

 

[Fishfinder]

What is this pipe?

 

[ca1ore]

My guess would be something amiss with the durso drain (getting airlocked as example). It’s odd that the water level is materially above the top of the drain assembly. Might try choking the return pump a bit or temporarily remove the double elbows from the durso to see if that helps with levels. You don’t have a valve on the drain do you? You also might want to consider turning both pipes in the overflow into a herbie-style drain. Then over the rim for your return. The marineland megaflow approach megasucks (I’ve had a number of their tanks).

 

[WVNed]

Is your drain vented at the top?

 

[joe1133]

What is this pipe?

It's the return pipe attacked to loc-line.

 

[joe1133]

Is your drain vented at the top?

It is vented. There are two vent holes. They are quite a bit under the water though. When they're not under the water, the overflow is VERY loud with water trickle sounds.

 

[joe1133]

My guess would be something amiss with the durso drain (getting airlocked as example). It’s odd that the water level is materially above the top of the drain assembly. Might try choking the return pump a bit or temporarily remove the double elbows from the durso to see if that helps with levels. You don’t have a valve on the drain do you? You also might want to consider turning both pipes in the overflow into a herbie-style drain. Then over the rim for your return. The marineland megaflow approach megasucks (I’ve had a number of their tanks).

I have the water level so high because when it is lower, I hear a constant loud trickling. I do have valves on both my drain and return line, but this seems to be the only water level I can have that doesn't overflow my sump if the power is turned off. I could try to open the durso to see if it helps and speed up the return pump?

 

[albano]

IMO, there is no way that your overflow should have such a high water level... you need to drop the drain pipes down at least 5-6 inches, maybe more!

 

[C. Eymann]

It is vented. There are two vent holes. They are quite a bit under the water though. When they're not under the water, the overflow is VERY loud with water trickle sounds.

I'd replace that 90 with a T + drilled cap fitting

 

[WVNed]

If your vents are under water your drain isn't vented. You are running a single full siphon drain. I have never been able to make one of those work.

I belive they way that is supposed to work is the water level in the overflow should be above the large hole in the side but below the hole in the top. The top hole lets air go in and out of the drain.

 

[Fishfinder]

Open the valve up on the drain. Get that vent hole above the water line. It’s not venting right now. Your display level is changing because your drain pipes are so high. The water level in the overflow needs to be lower

 

[Brew12]

If your vents are under water your drain isn't vented. You are running a single full siphon drain. I have never been able to make one of those work.

I belive they way that is supposed to work is the water level in the overflow should be above the large hole in the side but below the hole in the top. The top hole lets air go in and out of the drain.

Agreed. It doesn't take much for a system like this to have serious level issues.

A Durso will never be completely quiet but you can do some things to help but the water should never be above that air hole. That is an emergency feature with durso drains.

To tune your durso drains takes a few steps starting with setting your return pump for the flow you want with the durso valve wide open. Once you get the flow you want it's time to work at getting it quiet. You will want to close down on the durso valve but not so much as to cause level in the overflow to rise. This should quiet it a little. Then you can play around with the size of the air hole to try and quiet it further. Back when I ran a Durso I drilled a second hole and then blocked half of it with epoxy before I got mine relatively quiet. After you do what you can with the size of the air hole you need to give it time. As things slime up and age it will get a little quieter.

The emergency overflow protection of these things happens when the water level gets above the air hole. This shifts the drain from partial siphon to full siphon which allows much more water to flow and prevents the tank from overfilling.

 

[ca1ore]

I have the water level so high because when it is lower, I hear a constant loud trickling. I do have valves on both my drain and return line, but this seems to be the only water level I can have that doesn't overflow my sump if the power is turned off. I could try to open the durso to see if it helps and speed up the return pump?

As others have noted, the drain is the problem. Don’t speed up the pump, just open up the drain and your level problems will be gone. Noise is always an issue with the durso.

 

[joe1133]

Agreed. It doesn't take much for a system like this to have serious level issues.

A Durso will never be completely quiet but you can do some things to help but the water should never be above that air hole. That is an emergency feature with durso drains.

To tune your durso drains takes a few steps starting with setting your return pump for the flow you want with the durso valve wide open. Once you get the flow you want it's time to work at getting it quiet. You will want to close down on the durso valve but not so much as to cause level in the overflow to rise. This should quiet it a little. Then you can play around with the size of the air hole to try and quiet it further. Back when I ran a Durso I drilled a second hole and then blocked half of it with epoxy before I got mine relatively quiet. After you do what you can with the size of the air hole you need to give it time. As things slime up and age it will get a little quieter.

The emergency overflow protection of these things happens when the water level gets above the air hole. This shifts the drain from partial siphon to full siphon which allows much more water to flow and prevents the tank from overfilling.

Great! Thank you so much! So, you would suggest that I open the durso valve to lower the water level in the overflow, then adjust the return pump. I think the noise that was bothering me when I had it like this at first was the water flowing over the weirs and splashing down into the overflow. Is there any easy way to make this quiet?

The tank is in my living room area, and I need it to be as quiet as possible. Is it possible to reduce the splashing sound, or is that something I would need a different type of drain to accomplish?

 

[joe1133]

I've read a lot of posts about full-siphon being one of the main ways to make a durso and the overflow weir quiet, but what I'm hearing from all of you is that I need to change the water level (with the vent open to the air) so that it is not full-siphon.

I guess I'm just worried about the noise from the water splashing over the weirs since it is in my living room area. Then, of course...I'm hoping the durso itself doesn't sound like a flushing toilet noise.

Man! This stuff just feels so complicated. Thank you for all of your help so far.