How do you auto fill your ATO?

[atnet360]

I want to automate the filling of my ATO from my RO/DI.
Pretty much I want an ato for my ato.

I have the FMM with two available ports (3, 4) and the DC24 accessory port is available for the solenoid.
Can I run a line from the RO/DI to a float valve (redundancy) put the Apex solenoid in line and have two optical sensors regulate on and off?
One sensor on the bottom of the ato to trigger the solenoid to open so the ato can fill and the other sensor on top to close the solenoid when ato is full? The float valve is an additional fail safe.
I want the ato get nearly empty before the RO/DI unit fills it back up. That way I don't have a lot of tds creep and the RO/DI only turns on once about every 6 days.

I have a separate ato pump that takes care of ato to tank.
I am looking for the solenoid and optical sensors to take care of filling the ato itself.

This is exactly what I've done with my set-up. Been working perfectly for almost a year.

I actually have two tanks using the same ato reservoir, plus I feed my Kalk sirrer from the same reservoir.

When the water level in the reservoir drops below the lower optical eye, thr solenoid opens and it closes after the water covers the upper optical eye.

I placed the lower eye high enough that me ato pumps always remain submerged.