1)How much maintenance is a guinea pig in comparison of the pets I have?
A guinea pig will need its cage cleaned once a week at least. Daily veggies from an approved safe list for guinea pigs (really simple). Snuggle time or outside time from its cage daily. Will need a solid bottomed cage (no wire).
2)What is the best pellets? What should I look for in pellets?
Lots of people order Oxbow Cavy Cuisine for their guinea pigs as it is a timothy based pellet. You want a pellet that does not have seeds, dried fruits or veggies, or colorful bits in it, just plain pellets with a stabailized vitamin C in it.
3)Are they aggressive?
I've not had one grace my door yet and I have had many come through my door. They are extremely social creatures and are normally happy with one of their own kind preferably the same sex. I do not reccommend the bun and pig playing together if you do get it, as one kick from the bun could be fatal.
4)Any reason why I should or should not get a guinea pig?
Go here and read some of their requirements, only you know if you should get one or not. www.guinealynx.info www.cavyspirit.com
5)I heard something about them needing vitamin C....where do I get that...? Do they need supplement? They get their vitamin C from the fresh veggies you should be offering them daily. Some will eat the Oxbow vitamin C tablets, and other will sip it out of a syringe (liquid vitamin C) to get it. They can get scurvy like us, and their leafy greens is where they get the vitamin C from.
Ummm, anything else?