Pleas help me diagnose!

Thanks for looking at my post, please tell me what this is? I thought a mag prob I have been adding cal Mag and spraying Epsom salt on the foliar for a couple days new growth still looking like it can go to this color. And also new growth leaves turning upwards it seems. Please let me know what you think. Also I have 4 plants on the same system and the other 3 don't look as bad.


This is a hydro dwc grow. Reservoir 71. Air temp 79-81 rh 46 ph 6.0 1080 ppm using Lucas formula.

Thanks for any pointers!!

It does look like a magnesium deficiency. PH sounds good, possibly a Phosphorous excess causing Cal Mag lockout/deficiency? Nice and green otherwise, too much P?

I would agree it looks like Mg...a lot of the older undergrowth is pretty yellow and it is starting to progress up to the newer leaves. However, with CalMag and Epsom salts...you may want to see what is possibly locking it out. Interestingly enough, I have seen some 'professional' opinions and some say too much Ca can be an issue in detouring uptake of Mg. You may also want to get a an E.C. meter. If it is too high that may be an issue as well.

I give you mad props...awesome grow!

Indica dominant from the looks...strain?

Your pH is high I believe thiis causing odd grwoth so you are having to supplement extra Calcium which is pushing out Phosphorus. A problem I see is people use different nutrient solutions from one watering cycle to the next because which is is bad.. Do you remember hearing some strains are hard to grow, not for beginners? This is 100% of the secret "green thumbs" so here it is. Marijuana is sensitive to environmental change. A plant is almost as sensitive to rapid environmental change as a fish. A fish can't handle any changes in it's environment, for example, if you place a fish from 70F water into 75F water the fish will die. The secret to growing is the same as the secret to maintaining fish. You need a stable, consistent and dependable nutrient feeding schedule. You need temps/humidity to always be spot on. When everything is correct you shouldn't be running into this types of problems.

Just saying but usually people put epsom in the water ...and do cal mag as a foliar ...just thought I'd mention that since your doing it reverse ....good luck

I dunno about pH being the issue OP, it looks like you've managed very well thus far. I just glanced over the Lucas Formula, no grow used, high P using bloom from the start? I'm thinking it's a magnesium lockout,