Not to hijack Phenom's thread, but what if my tap is 700PPM??? After adding nutes it will bring the PPM up pretty high. Is my only option RO water?? Using municipal tap water, I have no idea what "parts" are in the PPM of my tap. Is it not better to get low PPM distilled water (if I have no access to RO) where I can control what parts are actually in the water? I am wanting an RO system and will get one soon. I do understand in more mature plants, a higher PPM is more desirable, but is that a safe PPM mixture for younger plants?

Sorry for all the questions, and like I said...I don't want to hijack a thread. I'm just trying to nail this PPM thing down.

*junk