Internal overflow issue

[dblimousine]

Hello community. Hoping for some sound advice and solutions to my overflow box issue.

I have a 120 gallon Aquarium Masters tank with built in corner overflow box and an Eshopps WE 150CS sump.

Problem: The overflow box teeth allow the tank water to drain (when the pump turns off), 2" below the normal water line thus filling up my sump. When pump is on it normalizes even though the sump is still a bit above the recommended water level line. As soon as you stop the pump it just keeps draining until 2" of air is exposed at tank line & sump fills almost all the way up.

What can I do to normalize this?

 

[JUNBUG361]

Your return pump is in full siphon. Check the return line nozzle in the display tank make sure it's set on the surface of the water level

 

[JUNBUG361]

Or you have too much water in your sump/fuge

 

[dblimousine]

Okay I will look into those two things.

Question: ultimately isn't the position or height of the teeth of the overflow box determining where the water line will be? Meaning if your overflow spillover is low then your water line will be low?

If that's the case, wouldn't i need to raise up the overflow box spill line by covering up the holes in the teeth of the overflow box?

 

[MG98]

It sounds line you need a standpipe. Look up Herbie, Durso, and beananimal setups.

The height of the overflow teeth does not determine the water level when the pump shuts off unless you have no standpipe in the overflow (in which case the entire overflow will gravity drain). When the pump shuts off the following will occur:

1. The water in the overflow drains below the level of the overflow pipe opening.
2. The water in the main tank is siphoned back into the sump through the pipe connected to the pump.

You can fix by adjusting the height of your overflow standpipe upward to allow less water from the overflow into the sump.

And/Or

Raise the nozzle of the pipe that is delivering water from the sump into the tank upwards.


In both cases you are exposing the pipes to air so you stop drainage and break any siphon.

Another trick is to drill a small hole in the pipe (near the surface of the water) that returns water from the sump into the tank. This hole is normally submerged but as the water drains, the hole will be exposed to the air to break the siphon. If your nozzles point down, they may be several inches below the waterline which will prolong siphoning when the pump shuts off. Make sure to drill the hole facing down so you don't blast water out of the tank.

I may be misunderstanding your problem but If you post a picture of your tank it can help diagnose the issue.

 

[PilotMaximus]

Okay I will look into those two things.

Question: ultimately isn't the position or height of the teeth of the overflow box determining where the water line will be? Meaning if your overflow spillover is low then your water line will be low?

If that's the case, wouldn't i need to raise up the overflow box spill line by covering up the holes in the teeth of the overflow box?

Well...it would not matter how high your overflow box spill over is if your return lines are too far below the water line in you display tank. Think of it this way. Even if you somehow raised your overflows up you could still siphon out water with a hose to do water changes couldn't you? You could even siphon that water right into your sump instead of a bucket right? Well that's exactly what happens as soon as your pumps stop pushing water up through them. Water siphons down into your sump and keeps on going until the return is above the water line. If there isn't enough room in your sump........flood. So you might need to raise your return outlets not your over flows and after doing so double check to see if your sump will hold all the water after the pump stops. If it doesn't just remove some water.

 

[dblimousine]

Thank you for all the insight. I will post a pic/video shortly. I get the siphoning explanation. Maybe I'm wrong but it seems like it's my overflow box that keeps draining not the return pipe siphoning.

To be continued. Frustrating!

 

[dblimousine]

Okay. So return pipe spray heads are completely out of water, 1/2-3/4 inches above waterline and tank is still draining until waterline drops below lowest level of the overflow intake??

 

[MG98]

how does water move from the overflow into your sump? Standpipe? Open drain at bottom of the overflow?

Water is either siphoning or draining from the overflow it sounds like.

 

[billdogg]

pictures will help a lot. If your return output is at or above the water surface that rules it out as a source of drain down. FWIW - most people have the return just below the surface but angled up to agitate the surface because that is where the majority of oxygen exchange occurs. Having them above the surface will create a huge amount of salt spray that can easily be avoided.

My question is this - Just how long are your overflow teeth that they allow 2" of drain back to the sump? Most overflows with teeth have them being maybe 1" tall, and the water level doesn't go to the top of them, so you would be looking at maybe 1/2 - 3/4" drain down.

Once again - pictures of the overflow box, the return line and the sump would help immensely.

 

[dblimousine]

Pic

Pic

Pic

 

[dblimousine]

Hope that helps. Teeth of overflow box are 2.5 inches from bottom to top. So waterline has 2.5 inches of gap showing. Waterline drains to lowest level of the teeth of the overflow box.

 

[dblimousine]

Pic

 

[dblimousine]

Waterline

Waterline

More pic

 

[dblimousine]

If I add water. Tank consistently comes back to this water level but my sump absorbs the extra water

 

[billdogg]

Those have to be the most ridiculously long overflow teeth I've ever seen. They also appear wide enough to suck many unsuspecting fish in. If it were mine, I'd replace it with something a bit more conventional.

Also - what's the pvc with elbow supposed to be for? It doesn't appear to be doing anything at all.

 

[MG98]

I can see the pvc elbow is connected to the black nozzles above the water line. Looks good there.

What I can't see is how h2o gets from the overflow to the sump. There's just a hint of white pvc in the overflow in the 2'nd pic. Is that a pipe? It looks well below the water level. I suspect that's the culprit.

 

[dblimousine]

Aquarium Masters overflow kit

Aquarium Masters overflow kit

K. So here is the drain pipe with elbow. The water is draining into the small hole to the sump. I will post another pic of inside of box where water is spilling thru the teeth. It just keeps coming until water gets to bottom of the teeth opening

 

[dblimousine]

Overflow

Overflow

Water seeping in from teeth. I can't raise the drain pipe any higher

 

[dblimousine]

Sump still rising

Sump still rising

Sump