i have 3 small rats on death row for the snake im getting tomorrow. i just put like 7 food pellets/cubes in for them last night and now they're all gone, lol. little piggies. do i keep food in there at all times? will they continue eating until they're fat or can i wait til tonight to give them more? the pet store told me 2 cubes p/ rat. i think if they keep eating like that i'll run out of food before the end of the month.