I have a chart I saved it from a previous post by someone helping me.
see attached.
Your plant looks like it shows two of the four characteristics listed for a Mag deficiency.
solution to mag def, 1 gram Epsom salts per gallon of water fed.
I learned this the hard way I was Lucky Qwizo stepped and gave me the solution in my case my plant was in flowering for more than 30 days before signs started.
The burnt leaves are still on my buds but the new growth is perfect.
I add one gram per every gallon I put in my resevoir.
Even when topping off the resevoir 1gr per Gal.
Just use a scale and add salts to hot water, once dissolved add the solution to your water then add your other foods if needed then PH the container.
If I was growing in soil (I'm growin in hydro)
I would keep two five gallon buckets of water side by side.
one stays water with a PH adjustment
the second would be the nutrient bucket including Epsom salts.
read your feeding schedule see how much your plant likes.
Start at 1/4 dose and work up to either a problem or the top of the schedule.
feed bucket 1 then wait till pot feels lighter by half then feed with bucket 2 and continue using this method to water. Misting under lights is bad in general the water magnifies the light and burn the leaf.
its even worse if Nutes are in the water then cooked on leaf.
Spray right after your lights go out if you want to foliar feed, lower temp means water will be absorbed not sweated off.
A PPM meter is a necessity for my hydro, maybe not everybody but I prefer to have the meter and be able to make exactly the food I want every time.