its up to you to discover what your plants can handle. if you do this and dont notice any nute burn your probably ok. the thing i would worry most about is salt deposites building in your soil from not using plain water. if this is the rout you choose to go and your plants respond well to it i would still flush/ not water, but fully flush the plant every once and a while. even if you dont see nute burn there is still a chance you could wind up with a over abundance of N P or K and thats a pain in the ass, because it wont be recognizable for a while. goodluck though. we grow, we live, and we learn.