[banditpowdercoat]

Mike, you do know that your TDS may be higher when just operating the RO/DI as top off water. You got the double solenoids for redundancy, cool, but the first Liter of my RO is allways higher in TDS. I find that making 20g at a time, then using that for ATO water, my TDS stays really low. But if I tap off the first liter, it's like >15PPM