Depends on the breed of guinea, how much space she has available etc. They need somewhere dark and fairly small to run and hide, as they are wimps, and they do have weak hearts. It's all to easy to scare them to death if they have nowhere to hide. They prefer a hidey hole full of hay to hide in, as then they can burrow. Never use straw with guinea pigs, as they can scratch their eyes, and for the males, little bits of straw can get stuck in their 'bits' which is nasty.
The more space you can make available in the hutch the better, as long as they have, as I said, a nice small dark area for hiding and sleeping.
Any guinea small animal advice - feel free to ask! Have kept all kinds of varieties for many years, including guineas, rats, gerbils, hamsters, bunnies etc. Ask away!
