ATO's

I was looking into getting an ATO because I can't keep up with my evaporation. But, I don't have a sump.
Can you run an ATO without a sump?
If you can what brand would you recommend?

 

I don’t see why you couldn’t ? I use a Kent Marine float that operates like a toilet bowl float with an airline connected to it with a siphon from a reserve tank. When the water drop’s the float drops breaking the seal on the siphon and the tank is replenished. Of course I do this in my sump so that there is nothing unsightly in my DT. I do not see why something like this would not work for you. BTW, this is like $15 so its worth the “test drive” if you will. You can spend a whole lot more and connect directly your RO/DI unit – this is something I have not done (yet).

 

I agree you can run it without a sump, you probably just want it coming into the tank in an area where it's not hitting anything directly.

Just be careful about setting up any kind of ATO, lots of tanks end up crashing, or at least overflowing, from malfunctioning float valves and a million other things that can go wrong with ATO's. Build redundancy into the float system or at the very least make sure the reservoir that your ATO is pulling from does not hold enough water to seriously affect your tank (salinity) if it all accidentally gets dumped in at once.