HYDRO Topping Off RDWC reservoir

[Slydog]

Okay my question is I'm using RO water to top off my reservoir in between weekly changes, should I be adding CalMag to my RO water? Currently week 7 of flower using GH Flora trio at 1200 ppm PH 6.2

[DW2]

Howdy Slydog, I do not use R/O water for my hydroponic grows, just ordinary tap water. But if one uses the R/O water, I should think that you would only have to adjust the pH to 6.5 before topping off the reservoir.

[Slydog]

Thanks DW2, Hopefully I can get some more feedback

[3Berries]

RO water will have little mineral content that actually will drive pH. So anything you add to it will change the pH to what the additive was for the most part.

So pH after nutes I would say. Add the non pH changing nutes afterwards. Like Epsom or other minerals.

What you don't want when adding Calmag is a low or high pH, -5 or+8. This will tend to strip the Ca+ and Mg+ out.