Gotta change your girls out......I usually let mine breed for about a year(max) then they are boa food......3-4 girls get replaced a month, as they are rotated, and never replace an entire tub at one time. Just the way I do things........2 years with the same breeders is like a woman having 20 kids and still having more at 45-50 years of age.....wait.....isn't there a show about that....?......all kidding aside, change your girls.....

Jason