Auto Top Off styles??

[Reef Pilot]

Originally Posted by Madmak

That's essentially what I do, very low risk, easy to use, and not many parts.

To cause a flood the solenoid would need to fail on AND the float valve would need to fail at the same time. That would still only cause a 15 minute fail, the timer would need to fail as well to lengthen that.

Cycling my RO system just means a few extra automatic membrane rises per day.

Yup, same here. I have a double manual float system in one sump and a double electronic float (from autotopoff.com) in the other, both feeding directly from my RO/DI output. I have solenoids which turn on every 6 hours for 10 minutes. And the failure mode for the solenoids is in the off position.

Very simple and reliable system. And my RODI has an auto shut-off valve, so no problem with the membrane.