Where does my water go?

[MnFish1]

I dont quite understand what you're saying. Do you mean that if you turn your return off (during a feeding) - the level in your sump goes up (it should) - and then when you turn the return back on - the level goes down to where it was before (in the sump) - or 4 inches lower than it was before (in the sump) - btw - just to be specific - I mean 4 inches below where it was BEFORE you did the feeding mode? Second question - does it stay lower or does it rapidly rise back it should be? Third - how big is your tank - and how big is your sump?

To (try) to answer your question - it cant be evaporation with a 5-30 minute feeding period. If you dont see water overflowing somewhere in your sump - it cant be that. If your overflow is somehow 'blocked' (either at the source - or somewhere in the pipe) - as the water from the sump flows back into the tank - the water level in the sump will drop - the tank will fill up faster than its draining - and thus - depending on how your ATO is set (and how long the tank takes to re-equilibrate) - eventually you can dilute out - eventually you will add enough water to the point where you tank will overflow.

PS - some other posts were added while I typed this - so I got most of the answers.

PPS - if what I'm saying is whats happening - as the water level in the sump is dropping - the water level in the tank should be higher than before the feeding (i.e. lower in the sump - higher in the tank) - until it re-equilibrates

 

[mtfish]

Ok, this is pretty crazy. So 10 minutes later the level is still low so you turn the ATO back on and lower the sensor so you don't add more makeup water. High alarm never comes back in.

Is there a chance you are back siphoning water somewhere? Have you verified your ATO container level isn't rising when this happens?

There could be something to this. If water does not stabilize in 10 to 15 minutes, then water could be going back into your ATO reservoir. FYI, the tube that feeds the sump from the ATO should ALWAYS be higher than the water level in the ATO to keep things like this from happening. On my tank, I run the tube up high and let it feed into a small PVC pipe so it can never back siphon. Does salinity change before and after powering off the pump? There has to be a simple solution, so I amend my first statement. Water has to either be going into the DT, sump or ATO reservoir.

 

[dduby]

Nothing is overflowing when you power down?
Water is not back siphoning into the top of reservoir?

Nothing is overflowing. The line from the ATO is above the water line, so i don't think it is a back siphon issue

 

[Brew12]

Nothing is overflowing. The line from the ATO is above the water line, so i don't think it is a back siphon issue

Does it stay above the waterline when the pump is turned off?

 

[MnFish1]

There could be something to this. If water does not stabilize in 10 to 15 minutes, then water could be going back into your ATO reservoir. FYI, the tube that feeds the sump from the ATO should ALWAYS be higher than the water level in the ATO to keep things like this from happening. On my tank, I run the tube up high and let it feed into a small PVC pipe so it can never back siphon. Does salinity change before and after powering off the pump? There has to be a simple solution, so I amend my first statement. Water has to either be going into the DT, sump or ATO reservoir.

I was just looking at my ATO - and there is no way a back siphon could even happen - when the water level is too high (i.e. when the return pump initially turns off and the water level rises - the ATO 'blocks' the flow of water in both directions). Thus I cant see how water would get into the ATO when the sump level rises - and when the sump level drops - the water level will be flowing from the ATO to the sump (right?)

 

[Brew12]

I was just looking at my ATO - and there is no way a back siphon could even happen - when the water level is too high (i.e. when the return pump initially turns off and the water level rises - the ATO 'blocks' the flow of water in both directions). Thus I cant see how water would get into the ATO when the sump level rises - and when the sump level drops - the water level will be flowing from the ATO to the sump (right?)

I've gotten water siphoned into my ATO from my sump before. My ATO container and sump are at the same level.

 

[MnFish1]

I've gotten water siphoned into my ATO from my sump before. My ATO container and sump are at the same level.

Isnt there usually a 'check valve' or something like that on the tubing? (seems like there should be). I think most ATO's are designed to be at the same level as the sump

 

[dduby]

Does it stay above the waterline when the pump is turned off?

I was just thinking about that, and i am not sure if it stays above water with the pump off. For a quick dirty test I checked TDS in the ATO and it reads 0. If i was getting tank water in my ATO i should read something above 0.

 

[mtfish]

You have me stumped. I would put a piece of tape or marker on the DT while running normal and see if it is higher after you turn the pump off and then on again (It may be a very little difference depending on how big the chamber in your ATO of the sump is). I run a Bean animal drain, but it is similar as there is a full siphon? It should not take 15 minutes to stabilize.

 

[Brew12]

I was just thinking about that, and i am not sure if it stays above water with the pump off. For a quick dirty test I checked TDS in the ATO and it reads 0. If i was getting tank water in my ATO i should read something above 0.

Agreed. If it has 0 TDS you don't have tank water siphoning there.

 

[mtfish]

Isnt there usually a 'check valve' or something like that on the tubing? (seems like there should be). I think most ATO's are designed to be at the same level as the sump

No check valve on mine. Strictly DIY design. But my tube is higher than either sump water or ATO water level, so cannot back siphon. Not sure about OP.

 

[dduby]

You have me stumped. I would put a piece of tape or marker on the DT while running normal and see if it is higher after you turn the pump off and then on again (It may be a very little difference depending on how big the chamber in your ATO of the sump is). I run a Bean animal drain, but it is similar as there is a full siphon? It should not take 15 minutes to stabilize.

LOL, that makes two of us. My plan is to power everything down and watch the ATO and see if there is any back siphon. I'd agree that is shouldn't take 15 minutes to stabilize but it was just part of my troubleshooting process.

 

[mtfish]

If we can just reverse engineer this problem, we could solve the world's water crisis! lol!

 

[SeaJay]

Mine does the same thing and I don’t have an ATO hooked up yet. Just a tank with dual corner overflows, a sump and two return pumps in the sump. Everyone is getting hung up on the ato, but I don’t think that has anything at all to do with it.

 

[shred5]

I was just looking at my ATO - and there is no way a back siphon could even happen - when the water level is too high (i.e. when the return pump initially turns off and the water level rises - the ATO 'blocks' the flow of water in both directions). Thus I cant see how water would get into the ATO when the sump level rises - and when the sump level drops - the water level will be flowing from the ATO to the sump (right?)

If there is no check valve it can happen easily depending on the ato container water height....

If water is lower in the ATO container than the sump and the ATO turns on, a backwards siphon could start when the pump shuts off if the supply tubing is submersed.. The thing is the ATO should not be turning on because the water level should be rising.. The supply tubing for the ATO should never be submersed though. You should check that...

 

[SeaJay]

The answer to the original question is, it’s in your display.

Why the pumps push it to the display faster than it can drain back down after we power the pumps back up is the real question.

I frequently have to do my top off right after a feeding, but only if I’m close to being due for a top off anyway. Mine may drop an inch or two from where it was before after I turn the pumps back on.

 

[mtfish]

The answer to the original question is, it’s in your display.

Why the pumps push it to the display faster than it can drain back down after we power the pumps back up is the real question.

I agree. I have not used a herbie overflow and am not familiar on how to tune them. I has to be that the pump is pushing water faster than it can flow back to the sump. Since it does not look like the OP is using a DC pump where you can vary the voltage, they could put a valve on the return line to adjust flow and see if it makes a difference.

 

[dduby]

just confirmed that the water is not going into the overflow. I pulled the supply line from the ATO pump and turned off the return pump and got no water from the sump.

 

[Shluffer]

A guess. Without knowing more........

Your return is a siphon. When you turn your pump on water is pushed to the dt. You start with a normal flow to your sump, which isnt fast enough to stabilize the water levels. So what happens:
Water goes to DT. Water level increases slowly because drain to sump is almost enough to not siphon or something prevents the siphon from establishing quickly. As the level rises an air block somewhere resolves and your return speeds up
Your sump water level increase 4 inches.

Probably goes up and down to an extent and eventually stabilizes. I had this on one of my tanks at one point, but was intentional by design. Eventually I realized it served no purpose so I fixed it.

 

[dduby]

Since it does not look like the OP is using a DC pump

I am actually I'm running a VarioS-6 pump. But after time if my return was out-flowing my drains wouldn't i start taking more water into the emergency drains, as well as suck the return chamber dry. The level is consistent until i shut everything off.