Every day I throw scratch in my run and put out treats (usually veggie & fruit scraps). The girls usually don't finish the treats, so I let them stay out a day or two. I rake up the run every couple of days or so. Today I went out to a TON of flies & a few bees buzzing around yesterday's watermelon rinds & the chick poo. I would like to have a nice clean run. How long can scraps stay out? Will they get infested with something and make the chicks sick? How often should I be raking it out?? I have a dirt floor that I sprinkle with DE once in a while. Thanks!