oops i ment adult mice a bit smaller than rats. At a young age I dont know how healthy it is to feed every 2 weeks. I guess if he keeps growing and gaining waight its ok but not ideal. They can go longer inbetween meals if they have more body mass. Do you buy feeders from a pet store? If so it is way cheeper to buy frozen online in bulk. I use rodentpros and a bag of 50 after shipping works out to about 60 cents per mouse. When I was broke thats what I did. Shipping is spendy but in the end its far cheeper.