Among the larger, more exploratory rodents kept as pets, rats require larger cages than smaller cousins like mice, hamsters and gerbils. The ASPCA suggests a multi-tiered wire ferret cage makes a perfect, spacious, enjoyable, well-ventilated habitat for pet rats.Converting a ferret cage for use with rats is neither complicated nor expensive. It's mostly a matter of removing ferret fixtures and replacing them with items appropriate for rats.
Add solid flooring to your ferret cage if it doesn't already have it, as your rats won't enjoy scampering around on wire, which can hurt them. Use linoleum tile, cloth place mats or another material you can easily remove and clean. Don't use plastic, though, because your rats will chew it.
Fill the bottom of the cage with soft bedding. Ferrets prefer towels, cloths, shirts and other large, soft material in their cages; rats like to burrow in pelleted paper bedding or aspen shavings. Never use pine or cedar, which can harm rodents. Add a couple undyed paper towels or a yard of toilet paper for your rats to shred and make beds out of.
Provide a smaller water bottle designed for rats if a larger one for ferrets is attached to the cage. Because the bottle attaches outside the cage and the metal drinking stem bends into the cage, the size of the hole provided for the water bottle should not be a concern.
Add an exercise wheel into the cage when you're using it for rats. While ferrets don't use these for physical activity, they're an important source of exercise and stimulation for rats. Use a solid wheel -- not wire -- so your rats' feet and tail don't get caught and injured. Make sure the wheel's diameter is large enough that your rats' backs don't arch when they run on it.
Include small boxes, commercially made rodent houses, upside-down flower pots with holes in the side, or other little homes for your rats to sleep in. Like ferrets, rats like to retreat to cozy, enclosed areas, but the latter prefer significantly smaller spaces than the former.
Place pieces of untreated, unpainted wood or commercially available chew toys in your converted rat cage. These would interest ferrets little or not at all, but rats need such items to keep their always-growing teeth worn down.
Replace ferret ladders in the cage with smaller ladders made for rats. Both animals love to climb ladders between tiers in their cages, but the differences in the length of their legs and the size of their feet require a different size of ladder for each animal.
Include tunnels for your rats to run through. While ferrets generally tunnel through towels, shirts, cloths and similar material, rats love more literal versions, and appropriate tubes for rats are small enough to fit in their cage. Use commercially available tunnels made for rats and mice, empty cardboard toilet paper and paper towel tubes or PVC pipes.
Scatter appropriate toys from a pet store around the cage to keep your rats entertained. Rats need stimulation and easily become bored. Don't put anything on upper tiers that can be pushed off, possibly injuring other rats below, though.
Keep your rat cage in the same place you kept it when it was in use as a ferret cage, if applicable. Ferrets and rats have similar sensitivities to light, heat, cold and drafts. Keep the cage away from sources of these. Neither pet likes to be completely isolated from the people in the home. Ferrets tend to be most active during twilight hours, rats make more noise overnight, especially on their exercise wheel. Consider this if you're planning to keep the converted cage in a bedroom.
rats image by Olga Barbakadze from Fotolia.com
Eric Mohrman has been a freelance writer since 2007, focusing on travel, food and lifestyle stories. His creative writing is also widely published. He lives in Orlando, Florida.