Hi, My sister bought me a mini cactus in July and i think it's starting to rot. The rot is only at the top but i'm concerned that it might be too late. I could have been overwatering but i also live in a dorm so it's hard to give it enough sun (i stopped watering it when parts of the top turned brown/black). I'm bringing it home so it will get better care. Any ideas? I'll post a picture too Thanks!
The photo is a bit blurry, but yes, it looks dead. I don't think you have overwatered it, the grafting stock would have gone first if you had.
I agree about the bottom rotting first, if over-watering was the problem. You might want to check for small pest like scale, spidermites or something else that could be doing the damage.
