Im using tap water that comes from a natural spring. The water company adds chlorine and it contains calcium. After aerating for 48hrs, the ppm go from 125 to 80. My plant havent protested a bit. That, and no need for Cal/Mag additives in my nutrients. I would think you can run it. Cept for the slight buildup of minerals on your equipment, shouldnt bother the plants. Oh, and ph'ing hard water takes a bit more ph down. I use AN down, but any you use properly will work for ya. Still, all this is better than buying water from the store. I wish i could have RO water at all times, but im small time. Perhaps someone else grows with ppm that is closer to yours. anyone?? Best of luck to ya.