Looks like nute burn. Advanced nute burn. If in soil use just water til it slows down. In hydro back off the nutes. I worry I see some sort of fungal infection possibly too. May want to look up leaf septoria and compare. But mostly just over fed to the point the leaves are burning up
You’re over feeding your plant, the EC level is way too high, creating those micro random deficiencies and the tips burns. Check the EC of the the runoff.