It is total PPM that you target. I just spoke to the guys at Green Coast Hydro (very knowledgable store in Socal) and they confirmed it for me. This is one of the main reasons for using RO water -- so that you can add more nutes to achieve the total PPM. Right now my tap water is just under 300 PPM alone, so going to RO water will allow me to add 33% more nutes since my target PPM is 1200. (currently water = 300 PPM) + (nutes = 900 PPM) = (Total PPM of 1200)... Got it?

Also, add micronutients, then additives (root conditioner, sweet, etc), then your grow/bloom in that order keeping tabs on PPM as you add ingredients.

Happy hydro growing folks!

MVP :jointsmile:
MVP Reviewed by MVP on . Base PPM and Nutes Something I haven't been able to figure out is... Lets say PPM of tap water is 200, vs RO water which could be 50... if wanted my PPM to be 400 for my reservoir, and Im using tap water with a base of 200 already, Then I would only be able to put as much nutrients in to make it 400, right? But if i was using water if a base of 50 PPM, then I would have 150 extra PPM of nutrients? So does it slow down growth by using water with a high base PPM since you can't add as much nutrients? or Rating: 5