Trigger a zone valve on/off from a double float switch

[escl8r]

I'm describing an automated pool top off, with the exception, the water source is remote from the actual float switch.

So I have a reservoir to a water feature that I need to auto top off. I purchased a double float vertical switch that allows an 18" drop in water before it makes a switch change.

Let's throw out the double float switch that just complicates things more and lets' just say single floater. How do I connect the float to the Hydroflash to trigger a specific zone to turn on and off? Don't know if the Insteon Serial link will work in this case or if there's any solution. Thanks!