Hi, we are the proud new owners of Peanut and Toffee, two gorgeous baby girls. We purchased the guinea pigs last week in the Ferplast 100 guinea pig cage measuring 46 x 95 x 57cm. It's quickly become obvious they need more indoor space to roam. Has anyone purchased an extension cage for this product (would another CC cage work to attach?). I am concerned the guinea pigs would have to jump over the high base of the Ferplast to get into an extension cage. Any help would be appreciated for a novice owner. Thank you Maria x