Based on our experience these are the 2 most effective rat racks. Which one is best for you will depend upon the ceiling height and your height.

Each large tub will hold 1 male to 4 or 5 females (breeding), Each small tub will hold 1 male to 3 or 4 females (breeding). Used as a holding or grow out rack each tub will hold 10 smalls, 6-8 mediums, or 5 larges.

One other point not often touched upon is that rats and mice will control their numbers. If the space is too small they will cull younger animals to conserve resources. The average number of pinkies that survive in each of these tubs, for me, is 34.

The food slot is designed to hold 3 -3.5 lbs of lab block,this will feed a nursing tub for about 1 week.

You will notice that most pictures are of currently used racks or tubs. We do this to show examples of how you may want to use them.

Building materials: as 2x2's are prone to twisting and bowing, we use 2x4's cut in half. We feel that this will provide you with a more stable rack. Also as we are building with wood there may be some variance.