We have a bunch of mealworms living in oatmeal. I already changed their potatoe once before, and the new one looks like it needs to be changed. Today I picked up a half and heard a little pop. When I looked at the bottom I saw yellow stuff that had connected the potatoe to the bottom of the bucket. I think I might have killed some pupating mealworms (needless to say the ones nearby weren't happy with me). I put the potatoe half back, but I was wondering if anyone knows what the yellow stuff is.