Nutrient burn? Help me diagnose and give a solution, thanks

Blah. Hmmmm. So when you water with fertilizer you add salt ions to the medium. If the water dries up or evaporates before the salt is used it stays in the medium and will contribute to the Electrical conductivity of the medium the next time you add more it jist accumulates until your leaf tips start to show damage from osmotic stress. The slight curling up of your leaf margins tells me she is using water faster than it's available during a cycle. She is at some point running out of water to maintain cooling for the entire plant so she begins to sacrifice the edges of the margin tips as water is running low. The medium, can only handle so much salt ions at once. Don't do a week of starvation that might trigger autophagy. Buy your self a EC soil metre, measure your soil ec, use that reading to determine whether to water or add more fert. Adding more salts to a medium that is already at 1.8ms/cm is not good for anything. Flush, reset, refeed, make sure she isn't running not of water at end of long day. Medium should always stay between 0.3ms/cm and 1.8ms/cm to avoid tips getting damaged. Whenever your medium get low add more salts. But never exceed 1.8ms/cm.