Please help with my hydro grow

Thanks for looking at my post, please tell me what this is? I thought a mag prob I have been adding cal May 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!!

Dont use cal..

Use just mag, and u have heat probleem..

Heat can be a reason for the mag def..