Hi. I got this Alocasia in the summer, and it's been doing well for a few months with a few new leaves. I've been watering every 10-14 days or so. The last time I watered it was maybe a week ago, so the drooping leaves is a new thing after such a short period of time from the last watering. I've also attached a photo of the soil I took from the top. I'm not sure if that's mold I see? If so, how do I remedy that?  
  
Other potentially pertinent info. The plant gets east-facing indirect light. In the summer when the plant was doing well, the average temp in my apartment was between 70-80 degrees. These days it's closer to 65 and less light is coming because of the shorter days. I have radiator heating that has been kicking on now that the outside temps are 40-55, so the apartment is definitely drier, and sometimes I'll crack a window because it gets too hot. The plant is about 10 feet or so from that window, so I'm not sure if it is more affected by the outdoor air. I have the plant on a rock tray that I regularly fill with water, but I'm not sure if this is helpful or harmful. My inclination is to think that I should be watering it more regularly because of the drier air, but I haven't yet because I don't want to accidentally drown it. Any insight would be greatly appreciated!

Need guidance for my drooping Alocasia Ivory Coast