Dude you need to give more information. What's your medium What's your ph What's your ppm What lights are you using How high are they hung Ect ...
hard to tell from just one picture, but I don't think so. Your heat should be fine at 75 and 50rh is good. Lightburn is very tricky, and more and more I am thinking leaves with mag problems may actually be leaves with light problems. What lights and how close? What media and nutes and etc..? I'm not a doctor, I just like to guess if I think it will help.