Is this cal-mag deficiency?
Several leaves are starting to look like this one. Got some browning tips and curling up. Should I give her FoxFarm Bush Doctor cal-mag? I have some but hesitant to use it, because as a whole she looks okay. How many leaves should look like this before adding nutes?
Possibly. Could be a pH problem as well.
Have you tested the soil pH, ?
Look up how to do a slurry test on youtube.
Great advice from @Spiney_norman. This does look like calcium issue, but if ph is out of range could be plenty of calcium availability just locked out. Depending on your base nutrients count possibly just need higher ppm feedings too.