Tunze osmolator 3155 ATO - trouble shooting

Idech · Jul 10, 2023

My 3155 ATO regularly stops working (it’s in the display) but all I have to do is wipe the optical sensor to get rid of the film on it and it’s fine again for at least a week.

Tonight I noticed there is 1/4 inch water missing in the tank so I wiped the sensor as usual but the pump wouldn’t start. I unplugged it for 30 seconds and plugged it back. The pump went off as it is supposed to but it only stayed on a few seconds and never filled the tank.

I’m leaving soon for a few days so this needs to be addressed quickly. Am I right in thinking the problem is the optical sensor ? I think they are available separately for sale so I will look it up.

Thanks !

Hallowhead · Jul 10, 2023

If it's still under warranty, reach out to tunze. They are super fast and helpful !

Idech · Jul 10, 2023

Hallowhead said:
If it's still under warranty, reach out to tunze. They are super fast and helpful !

I’m in Canada and it really is a hassle. I‘m not 100% sure about the warranty, but if it’s 2 years, I have 11 days left…

Thanks for reminding me.

David_CO · Jul 11, 2023

you dosing kalk?

I had major issues with mine until i put a small powerhead in my return chamber under where my dosing lines are.
I went from having to clean the optical eye 2x a week to now where I havnt had to clean it in months.

Idech · Jul 11, 2023

David_CO said:
you dosing kalk?

I had major issues with mine until i put a small powerhead in my return chamber under where my dosing lines are.
I went from having to clean the optical eye 2x a week to now where I havnt had to clean it in months.

I only dose All for Reef manually with a seringe. I’ve been shooting half of it near the sensor, but never directly on it. Maybe that’s why.

The sensor is in the display (I don’t have a sump) and there’s lots of water agitation though.

I’m letting it sit in a 50/50 vinegar and water solution for the day. Hopefully it works tomorrow.

Idech · Jul 13, 2023

I’m happy to report that after soaking in a 50/50 vinegar and water solution for 12 hours, the sensor is working fine !

I’ll make sure to follow a strict maintenance schedule from now on.

codenfx · Jul 13, 2023

Idech said:
I’m happy to report that after soaking in a 50/50 vinegar and water solution for 12 hours, the sensor is working fine !

I’ll make sure to follow a strict maintenance schedule from now on.

I've had the same issue with my sensor, did a citric acid dip for 30 mins and all is well. Now I routinely clean it at least once every 3 months. The pump also had issues for a day or two and it was fine afterwards, no idea why but I got a spare replacement just in case it goes out.

Uncle99 · Jul 13, 2023

Have any snails?
They regularly covered my sensor and then left.
Baffled me.
I put a snail guard on it.
No further issues.

Lbrdsoxfan · Jul 13, 2023

The prism is usually the weak spot on any of those ATO's that use them.

InactionJackson · Jul 13, 2023

I’d invest in a new pump…just in case …..

Idech · Jul 13, 2023

Uncle99 said:
Have any snails?
They regularly covered my sensor and then left.
Baffled me.
I put a snail guard on it.
No further issues.

Yes I do but I’ve never seen a single one on it. It’s in my display, so pretty high.

InactionJackson said:
I’d invest in a new pump…just in case …..

The pump never stopped working but I won’t hesitate to get a new one if need be. They’re easy to find, contrary to the optical sensor that needs to be sent to Tunze for repair.