Like ferrets, guinea pigs are happier in groups. But choose your guinea pigs carefully! More than two males together may result in some fighting. Two females together are usually safe... and if you're housing one of each, watch out for baby piggies!
You may think a guinea pig will be an "easy" pet because it is small, but small pets need just as much care as big pets!
Make sure your guinea pig cage provides ample room for moving around. The bigger the cage, the more active your guinea pigs will be! The cage should be at least 18 inches wide and 25 inches deep. The cage floor will need to be lined, because their feet are very tender and wire can be painful. Line the cage with ink-free paper or buy commercial nesting material at your local pet store. The lining material will be bedding, bathroom, and occasional snack.
Did you know that guinea pigs' teeth are constantly growing? They will chew on anything and everything to keep their teeth worn down to a manageable length. Everything in the cage must be nontoxic.
Offer plenty of hay for nesting and nibbling. Your guinea pig will also need a branch to gnaw on -- try an untreated fruit tree branch.
Despite their small size, guinea pigs will need a lot of help with cleaning. Though they groom themselves frequently, your guinea pig may need frequent brushing -- especially if you picked a long-haired breed. And because their cage lining is both bedding and bathroom, you will need to change the litter frequently.
Make sure your guinea pig has access to water at all times. A water bottle with a sipper tube will attach nicely to the cage, but be sure to clean the bottle and tube daily to prevent the growth of bacteria. Food and water bowls should be heavy enough to resist tipping. And make sure your guinea pig gets a lot of fresh veggies in her diet -- kale and cabbage are rich in Vitamin C. She may also like an occasional slice of melon or apple. Just be sure to remove the seeds first!
Last but not least, your guinea pig home needs some entertainment! They may like platforms to climb on or tunnels to crawl through.