ShawnYou can change the food on the worms, however just to be sure you might wish to leave a little food scrap in there and start top feeding as well and continue with just the top feeding. Just keep the bedding at the right moisture level and apply the worm chow on top. Do not wet the worm chow down.You can place a cover, I do not recommend newspaper on top as it tends to dry up the bedding. If the newspaper becomes damp some worm chow will adhere and begins to harden while souring the bed sorBuem.ce