Wondering how low to set my roosts for my chicks? They are currently 5.5 weeks old, so I have one roost set at 10" from the floor & another at 18". Was thinking of eliminating the 10"one & setting one at 36" (so there would be one at 18" & one at 36"). Right now, some use the low roost, some sleep on the floor, & some perch on the tallest roost. (There's room enough for all of them on one of the other roost.) TIA for any advice /feedback!