Auto Top off problem

[TheTangFuzz]

I have an auto top off that I just started using recently it's an IceCap one. It has two optical sensors one for water level and a backup. It was working perfectly fine for about a week and then I noticed this morning before work and yesterday morning that the water level in my tank was higher thank usual. This seemingly only stopped because the water in the auto top of was low enough to stop the pump. This of course lowered my salinity. My question is why is it overfilling and is there something I can do to stop it? The sensors seem clean. The auto top off is in the display tank (no sump) and while there is water movement it seems to be okay until just the past couple of days.

 

[Silent]

Being in the DT is there water surface agitation possibly messing with the sensor causing it to add more water than it should?

 

[TheTangFuzz]

Being in the DT is there water surface agitation possibly messing with the sensor causing it to add more water than it should?

There is surface agitation, but it seemed to fair well for the first week before these issues arose.

 

[Silent]

Not sure if that is the problem but if you think it could be you could add a piece of acrylic or something to shield it from waves. Put sensor in the corner surrounded by acrylic.

 

[TheTangFuzz]

Not sure if that is the problem but if you think it could be you could add a piece of acrylic or something to shield it from waves. Put sensor in the corner surrounded by acrylic.

How would I go about attaching the acrylic?

 

[Silent]

There are a number of ways you could to it. A small acrylic box with the bottom cut out, or just a straight piece clipped in the corner to make a triangle, or maybe use styrofoam instead of acrylic, anything that would block the waves from hitting the sensor.

 

[HK Chan]

I have an auto top off that I just started using recently it's an IceCap one. It has two optical sensors one for water level and a backup. It was working perfectly fine for about a week and then I noticed this morning before work and yesterday morning that the water level in my tank was higher thank usual. This seemingly only stopped because the water in the auto top of was low enough to stop the pump. This of course lowered my salinity. My question is why is it overfilling and is there something I can do to stop it? The sensors seem clean. The auto top off is in the display tank (no sump) and while there is water movement it seems to be okay until just the past couple of days.

Is your water tank higher than your main tank? Is it Siphon effect?

 

[Uncle99]

You have snails?
Famous for getting on optical sensor which will turn on ATO until water runs out, secondary float takes over, or snail moves.

I finally put a snail guard on my ATO. Three years now no problem.

Snail Guard (aka.....piece of plastic which rests 1/16 inch below optical sensor)
Then they can’t get to it.

 

[TheTangFuzz]

You have snails?
Famous for getting on optical sensor which will turn on ATO until water runs out, secondary float takes over, or snail moves.

I finally put a snail guard on my ATO. Three years now no problem.

Snail Guard (aka.....piece of plastic which rests 1/16 inch below optical sensor)
Then they can’t get to it.

I do have snails. I believe it was one of my turbo snails

 

[MzunguReef]

I had a similar issue recently. Couldn't work it out to start with and then realised than it would trigger whenever there was a shaft of sunlight from the window on it. I'm assuming the sunlight would somehow confuse the optical sensor causing it to trigger?! Anyone else experienced this? Is your sensor positioned somewhere that it might get some sunlight on it?