I'll be getting 20 LF chicks next week. They are a mix of Australorps, Barred Rocks, White Rocks and Easter Eggers. My brooder set up is a large plastic tote that measures approximately 3 ft x 1 1/2 ft. Would this be a sufficient size to brood the chicks in? And if so, how long would they theoretically be able to stay in there before being over crowded? Thanks!