Leaves drying and dying?

sooo i have done everything i can, things seem to have gotten a bit better but still not fixed. after loads of research i am coming to the conclusion that i may have a mg deficiency. what do you guys recommend to fix this, epsom salt? or should i go shell out some money for cal-mag or another product? plan on giving them some mg in a few days after they dry a bit from their transplant. Please help.

i am having th same problem the top leaves look great but the bottom leaves are draying can anybody tell me why thats happening and how can i fix it.