Deficiency or bad maintainence

99.9% of the times, when the tips burn like that, its an excess and not a deficiency, however you could have an excess causing a deficiency, that's something that happens. If you overfeed with P, K, Cal, and some more, im just saying these from memory, these will cause lockouts in other nutrients. Now... i can't tell yet what it could be from just these pictures, maybe some1 can but i can't, so if you happen to add more pictures of the affected leaves (burned, color changed, contorted, etc etc) then i can try and give it a go, but for now idk. But if you feed and the symptoms beggin to appear or continue developing, then you just gotta stick with water for a while for her to recover. Stay lit growmie.