After a couple of weeks it failed to trigger. After a quick unplug/plug it recognized it was low and filled up. Make sure to keep an eye on it! Otherwise a must have for a nano
This is my first ATO, and I can't saying anything bad about this product. I no longer worry (overly) about my salinity changing due to evaporation. if this product goes defunct, I probably will upgrade to the non-nano version, but Tunze has a quality ATO product for those with nano systems.
Love this little ATO, been using mine for 2 1/2 years with no issues.
still going after 2 years. a little noisy, but reliable.
Good product but auto top off version is better.