Oh boy! We're at 800ppm before my RO system treats it with 180+ grain. We get algae blooms in our toilets that can kill animals and make people get sick. When I first started growing here the water was at 180ppm them a few years later it remained over 500. pH stays over 8.8.
@SHRED I'd use that RO system because should an issue arise, you can normally rule out your water as a problem. I was able to make it to mid flower on 500ppms but would lose all my leaves within two weeks. If I ever have issues now it is not because of my water with the RO system.