burn, too much potassium( lower older leaves interveinal chlorosis) too much K burns leaf edges and locks out magnesium, and looks to be too much phosphorus(tallest flowers leaves that are close to the light) too much P locks out zinc, then iron, then magnesium, in that order( tallest flower close to light)
more light demands more food and it seems to bring out the toxicity, low light, potassium toxicity wont show up as easy for whatever reason
i have first hand experience with this, less food next time bro