One of the more common questions new guinea pig owners ask is "What do I put in the bottom of the cage?". Whatever material you decide to line your guinea pig cage with, it must perform a variety of functions. It must be absorbent and control odors. It must be comfortable for the guinea pig to walk on and provide decent insulation. And above all it must provide the guinea pig with an outlet for tendencies to dig, chew, and have fun!

Two common materials are definitely out as far as bedding is concerned: cedar and pine shavings are not recommended. In fact, they might be harmful to your guinea pigs health, so don't use them.

Aspen shavings are completely safe, however, and don’t have to a strong scent. Unfortunately, that means it will need to be changed frequently.

Timothy hay is probably the premier material for guinea pig bedding. Guinea pigs will tunnel through it, play with it and even eat it. Timothy hay bedding also smells nice.

A cheaper option is to use shredded newspaper. It’s absorbent, but has little odor reducing qualities....so it must be changed often, but it is essentially free.