I want to use an auto top off system for my tank to replace evaporated water. But I have no room for any type of reservoir. But I can run a line from my spectrapure RO\DI unit directly to the sump, and there is even a drain near the unit for the waste water. My question is first off is it possible to top off the tank using no reservoir? Second what solution would stop the RO\DI unit for producing waste water non stop. Is there an easy solution?