my bottom leaves always look like that, or worse :wtf: ... in my case, it's from my compulsive urge to over-water ... be sure she dries between watering, and otherwise, don't fret over it ... it looks pretty good overall, and more harm is usually done, by trying to correct minor annoyances like that ... imagine the difference between we over-indulgent 'parents', and that cruel bitch, Mother Nature ...