I ran into a mag deficiency growing some Ice and added 3 tablespoons to my system, which is about 50 gallons. That raised my pH by 50 ppm (500 scale) and stopped the problem. That raised my total ppm to around 400 at the time. If I were going to use it as part of my regular nute schedule, I probably wouldn't go as high.

Great, thanks RoeBuck,
I just wanted to experiment with it a bit. I have never used it yet, which seems crazy, but I still feel as though I am trying to find the sweet spot with feeding schedules. I know I am riding the line of over feeding a bit because I see a touch of tip burn pretty early in bloom, but by week 3-5 I also see mag def.
Maybe foliar is all I need? Maybe just the first few weeks of bloom then add some to Rez after that?

JMcG said:

Great, thanks RoeBuck,
I just wanted to experiment with it a bit. I have never used it yet, which seems crazy, but I still feel as though I am trying to find the sweet spot with feeding schedules. I know I am riding the line of over feeding a bit because I see a touch of tip burn pretty early in bloom, but by week 3-5 I also see mag def.
Maybe foliar is all I need? Maybe just the first few weeks of bloom then add some to Rez after that?

Click to expand...

Sorry to be so long replying, I haven't had time to get in here much lately.

A foliar might work depending on how bad the deficiency is. I've learned that less is more in these systems. When I first started I was following the published nute schedules and ran into problems with high ppm and eventually nute lockout. So now I stay a bit lower which gives me a little leeway should I run into a situation where I need to supplement with something like epsom salts. Right now I'm running some OG Kush that's just finishing stretch. ppm (500 scale) is around 375 and dropping 10 points or so a day. If I needed to add another 50 ppm of epsom salts I could do so without pushing it too high.

I typically add Epsom Salt at 1g/gal, I add it last as it does inflate your PPM, but not in a way that you will burn your plants if you add it last and you track your PPM on your normal feeding schedule.