I'm not sure what is happening, but more and more frequently I'm finding that my Tunze ATO is not keeping my tank topped off. A couple times a week I'm having to top off 2-4 gallons of RODI water myself as the water level has dropped and the ATO sensor doesn't seem to be recognizing that. I'm guessing the optical sensor is going bad? I've cleaned the sensor and soaked it in RODI / Vinegar water a couple times and still having problems. I'm to the point where I have to check the return pump chamber of my sump every morning and night to make sure its maintaining the desired water level.
I think it might be time to move on and try something new. The Tunze ATO has worked decently for me over the last 4 years, but I've had to replace the pump 3 times and now this most recent behavior that I've noticed. I'm thinking I might try a @Puratek Auto Level Controller instead of continuing to dork around with the Tunze ATO. I really like the option of having up to 3 water level sensors sitting on the outside of the sump.
Also forgot to mention that nearly all the bacteria slime is gone from the display. I've pulled one of the pipes out of the bulkhead in the overflow box and let all the nasty stuff that had settled back there drain into my filter socks as well. My nitrates seem to have stabilized around 2.5ppm, so everything seems to be going well!
I think it might be time to move on and try something new. The Tunze ATO has worked decently for me over the last 4 years, but I've had to replace the pump 3 times and now this most recent behavior that I've noticed. I'm thinking I might try a @Puratek Auto Level Controller instead of continuing to dork around with the Tunze ATO. I really like the option of having up to 3 water level sensors sitting on the outside of the sump.
Also forgot to mention that nearly all the bacteria slime is gone from the display. I've pulled one of the pipes out of the bulkhead in the overflow box and let all the nasty stuff that had settled back there drain into my filter socks as well. My nitrates seem to have stabilized around 2.5ppm, so everything seems to be going well!
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