Introducing Guinea Pigs

Question
Hello, I currently own 2 guinea pigs. I originaly had 1 but after a while we realized it was lonely, so bought another one. The one we bought was younger than our original guinea pig, by around a year. After a while, we introduced them to each other in the bottom half of the big clean cage. They circled each other and purred deeply, then they began to chase each other around and looked like they were biting each other, but i'm not sure. So we split them up and tried again a few weeks later. They done the same thing. I'm un sure if this is normal behavior or if this is bad, were they fighting or just inspecting each other? Also, we keep them in different cages beside each other, and sometimes they bite at the bars and purr, is this bad? Please help me, as i don't know if i should just by another cage for the newer guinea pig because he is getting too big.
Thanks a lot, Emma.

Answer
Ah, my piggys did the same when they first met. There are a few things you can do for this.
Try having them run around in a medium sized inclosure (large enough for you to sit in it with them and they still have room). You can buy play pens at almost any pet store. Sit in it with them both and have a medium sized towel (dish towel) ready to put it on top of one of them in case they start to fight. The key to them becoming friend is more time around each other, atleast once a day. Keep there cages about four inches apert from one another as well. When they start to get familiar with each other and fight a little less than put them both in the larger cage together but put a divider in the middle so they cannot seriously injure one another. Remember, the more they see each other, the less aggresive they will get.

Thanks for asking!
-Nicole