This brings up an interesting thought.
My ATO holds 5 gallons. My total system is 124 gallons including sump. There is more than enough room in my sump if the sensors failed and pumped all 5 gallons of RODI into the system. How much would this effect the salinity if, on the off chance my ATO failed, all 5 gallons ended up in the sump? Would it be enough of a change to wipe out my tank?