We use Mazuri pellets and our cavies love them. As far as hay we buy all kinds as long as it is fresh and green. We usually buy local hay but we also buy from Small Pet Select and Kaytee hays are usually good, inexpensive and easy to come by. Their vegetables are more important than the pellets and the hay comes after the veggies, so pellets are the least important. Also one thing that gets overlooked is fresh water daily! Do not buy a giant bottle that holds a lot of water - WHY you ask? because you are more likely to neglect changing, cleaning and filling it daily with fresh water is why. A bottle that will give them enough water for a day is all you need AND buy at least two of those. One will be a back up in case the other one fails, so you will actually have two days worth of water available at all times. You will see a lot of people here push for Oxbow, I almost believe they are getting kickbacks for them or something lol! Another good brand is KMS Hayloft! But due to their price I choose to stay away from them.