Would this work? Drip system? Kind of

[Pharaoh]

You could definitely use it as an auto top-off.

 

[sbrodacz]

The part I'm trying to figure out, is how do I get the water to pump from the smaller bin into my sump when the water level is low? I understand I could put a float valve in the sump. Is there an easy way to make this work?

 

[Pharaoh]

Just have a float valve in the sump. The float valve would be wired to a relay, which is also wired to the power for the pump. When the water level drops, switch activates the relay, relay activates the pump until the switch turns off.

 

[sbrodacz]

Sounds complicated.