Unstable water levels

huthain

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Hello all! So ive had my aquarium for 3 months now super happy with all the progress got all the bells and whistles i wanted too but I am really struggling with my water level. My aquarium is custom made it seems and I feed twice a day. While feeding all pumps are turned off and the gyre so I can target feed all my fish both times. Unfortunately almost every time I turn everything back on the water level fluctuates by a decent margin an inch or 2 most of the times and sometimes more.

This has ofcourse in the past caused issues with my ATO pouring in water unnecessarily leading to lowered salinity. I have turned off the ATO the last 2 weeks trying to manually add water while playing around with the adjustment but still no luck.
Initially I've wanted the water level in the weir to be flush under the openings at the top to allow for surface agitation or movement, now im experimenting with the water being right at the emergency overflow. But even then its fluctuating to into the overflow which means debris or detritus is going direct into the sump bypassing the roller.

Any suggestions on what I can do? Is it recommended i change something in my system? Is my valve not good? Pictures below for reference.

20251020_171743.jpg 20251020_171748.jpg 20251020_171751.jpg 20251020_172722.jpg 20251020_172719.jpg
 

Kooma

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That sounds pretty normal, it takes a little bit for the returns to fill the tank and for the drain to pickup like it should.

Personally I would simply leave everything on and feed slower in a corner away from the overflow. Feed as fast as they are eating it and if some go down the drain that’s fine, your roller has it covered.
 

Sawacoral

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I think controllers are helpful in this regard, as I personally can have stuff like ATOs skimmers and other equipment come back on after the water levels have stabilized in the sump. Or else you could have issues like you've mentioned. Or at least unplug your ato during feeding and plug it back in when you want. Some folks use smart outlets where you may be able to do that on a schedule or manage remotely.
Have your ATO come back on last, after your other equipment.
 
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huthain

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That sounds pretty normal, it takes a little bit for the returns to fill the tank and for the drain to pickup like it should.

Personally I would simply leave everything on and feed slower in a corner away from the overflow. Feed as fast as they are eating it and if some go down the drain that’s fine, your roller has it covered.
I would love nothing more than not closing everything during feeding but some of my fish are too dominating when it comes to food time so I really need to get in there. Otherwise my goby will grab everything and my blenny will struggle to pick any up.
On your first point I have this issue even if I wait for an hour or more for it to stabilise, the water can go significantly higher than what I set it to last time.
 
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huthain

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I think controllers are helpful in this regard, as I personally can have stuff like ATOs skimmers and other equipment come back on after the water levels have stabilized in the sump. Or else you could have issues like you've mentioned. Or at least unplug your ato during feeding and plug it back in when you want. Some folks use smart outlets where you may be able to do that on a schedule or manage remotely.
Have your ATO come back on last, after your other equipment.
Its not really the ATO that the issue, its the fact that the water rises was more than the last time it was running leading to the sump getting lower. If that issue didnt occur the ATO doesn't pump my sump with water.
 

X-37B

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First this should not happen.
Water level should not change from turning off the return.
My larger system 150 takes a few minutes to drop back to the running level.

I never turn off the return when feeding.
If you want just turn off internal gyre and powerheads with just the return on.
This will give you time to figure out the issue.
Skimmer will loose its head but that's normal.

Is this an ac or dc return pump?
 
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huthain

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First this should not happen.
Water level should not change from turning off the return.
My larger system 150 takes a few minutes to drop back to the running level.

I never turn off the return when feeding.
If you want just turn off internal gyre and powerheads with just the return on.
This will give you time to figure out the issue.
Skimmer will loose its head but that's normal.

Is this an ac or dc return pump?
The return is a DC pump, i think I may as well just try to do the feeding with the Gyre off and return pump on.
Dont see how else I can get rid of this issue. There are times I will turn it back on and it will return to the same level but also times it will go above what it was previously.
 

Steig

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Hello all! So ive had my aquarium for 3 months now super happy with all the progress got all the bells and whistles i wanted too but I am really struggling with my water level. My aquarium is custom made it seems and I feed twice a day. While feeding all pumps are turned off and the gyre so I can target feed all my fish both times. Unfortunately almost every time I turn everything back on the water level fluctuates by a decent margin an inch or 2 most of the times and sometimes more.

This has ofcourse in the past caused issues with my ATO pouring in water unnecessarily leading to lowered salinity. I have turned off the ATO the last 2 weeks trying to manually add water while playing around with the adjustment but still no luck.
Initially I've wanted the water level in the weir to be flush under the openings at the top to allow for surface agitation or movement, now im experimenting with the water being right at the emergency overflow. But even then its fluctuating to into the overflow which means debris or detritus is going direct into the sump bypassing the roller.

Any suggestions on what I can do? Is it recommended i change something in my system? Is my valve not good? Pictures below for reference.

20251020_171743.jpg 20251020_171748.jpg 20251020_171751.jpg 20251020_172722.jpg 20251020_172719.jpg
Add a shutoff valve in the overflow pipe
 

Steig

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Hello all! So ive had my aquarium for 3 months now super happy with all the progress got all the bells and whistles i wanted too but I am really struggling with my water level. My aquarium is custom made it seems and I feed twice a day. While feeding all pumps are turned off and the gyre so I can target feed all my fish both times. Unfortunately almost every time I turn everything back on the water level fluctuates by a decent margin an inch or 2 most of the times and sometimes more.

This has ofcourse in the past caused issues with my ATO pouring in water unnecessarily leading to lowered salinity. I have turned off the ATO the last 2 weeks trying to manually add water while playing around with the adjustment but still no luck.
Initially I've wanted the water level in the weir to be flush under the openings at the top to allow for surface agitation or movement, now im experimenting with the water being right at the emergency overflow. But even then its fluctuating to into the overflow which means debris or detritus is going direct into the sump bypassing the roller.

Any suggestions on what I can do? Is it recommended i change something in my system? Is my valve not good? Pictures below for reference.

20251020_171743.jpg 20251020_171748.jpg 20251020_171751.jpg 20251020_172722.jpg 20251020_172719.jpg
Add a shutoff valve in the overflow pipe
Just remember to open it when you turn everything back on or you will have a mess
 

X-37B

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The return is a DC pump, i think I may as well just try to do the feeding with the Gyre off and return pump on.
Dont see how else I can get rid of this issue. There are times I will turn it back on and it will return to the same level but also times it will go above what it was previously.
Sound like the dc pump is the issue. I run ac pumps for that reason. I know a few who say that their dc pumps fluctuate so maybe that's the issue.
What brand?
 
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huthain

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Sound like the dc pump is the issue. I run ac pumps for that reason. I know a few who say that their dc pumps fluctuate so maybe that's the issue.
What brand?
I believe its a Chinese brand, Sobo or Sebo. Should I try changing that out? Any recommendations? Most stuff I have is red sea should I get their return pump too?
 

X-37B

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I believe its a Chinese brand, Sobo or Sebo. Should I try changing that out? Any recommendations? Most stuff I have is red sea should I get their return pump too?
How big is the system. I run Tunze for 2 systems and sicci for another 2.
 
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huthain

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How big is the system. I run Tunze for 2 systems and sicci for another 2.
Not very big almost a 60cm cube, with about 250 liters of water or just under that. We dont have too many options where I am sadly, I know we have redsea here which is one of the better known brands I guess.

Could it be I need to clean my pump? I haven't done that since I got it under 3 months ago
 
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huthain

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Clean and see what it does.
Did it just start doing this?
I would get an ac pump.
Not sure what's available where you are.
I used to have an AC pump but my couldnt get rid of the water sound with it not sure why.
 

mboley

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It sounds to me like your overflow may be under- sized for the flow setting on your pump. Try turning down your pump.
 

BryanM

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So, I turn off the ATO, and return when I feed Fish. I leave the wavemakers on because they shoud work for their food IMO.

The ATO has a delay to come back on because the return pump takes 10min or so to stabilize (I only run a 1x-1.5x sump->tank turnover, so its slow). But after that, the ATO comes on and levels are good.

I think I'm a tad confused here in so much as if anything, your ATO shouldn't come back on after feeding anyway, as the sump should be "over full" until the return pump is done getting water back in to the display. So maybe that's what's fluctuating, and that does sound like a return pump issue to me.
 

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