No matter what kind of cage you choose for your hamster, be it a wire cage, plastic cage, or an aquarium, there are certain things that you must put in the cage in order to keep you hamster happy and stress free. Hamsters are extremely susceptible to stress so it's important you do all you can to keep your hamster happy. Simple things like choosing the right kind of bedding and nesting material, adding a hamster wheel, and a few toys will make a huge difference to your hamster's quality of life.
Bedding material serves two purposes: as a soft cushion for your hamster to walk on, but also to soak up urine. Hamsters love to burrow and dig so make sure you place at least two inches of material on the bottom of your hamster cage. The most common material used for bedding material is wood shavings, but it's important that you NEVER use Cedar shavings. Cedar shavings contain a chemical that can cause serious illness in your hamster, so it's best to avoid it altogether. Pine shavings are an option, but have been shown to cause allergic reactions in some hamsters. Your best bet is bedding material made from Aspen shavings or litter made from wood pulp. Also try to avoid any scented products ? it may smell great to you but your hamster's sensitive nose will not appreciate it.
You may think that simple cat litter would do, but the dust from the litter can cause respiratory issues for your hamster, and the tiny grains get caught in your hamster's feet causing irritation. Hamsters spend the entire day sleeping, so they like things comfy. They'll construct their nest out of whatever is available, including bedding material, but would prefer something a little softer. Shredded paper towel or bathroom tissue would be ideal, as long as it doesn't have dye and is unscented.
Although you may be tempted to supply your hamster with cotton for his nest this should be avoided at all times. The cotton strands can get wrapped around the hamster's limbs or neck, cutting off blood supply. Stick to bedding material or the shredded paper for nesting material.
Exercise wheels are a must have for your hamster cage. In the wild hamsters roam up to five miles every night in search of food, so whether they're in a cage or out in the desert they're going to feel the need to run! The most common hamster wheel that comes to mind is the wire frame wheel, with rungs laid across the length of the wheel. These can be very dangerous for your hamster, as a missed step can lead to the hamster putting his leg between the spokes while it's turning, thereby breaking his leg. The ideal choice is a hamster wheel with a solid base and entry holes instead of spokes. This greatly reduces the chance of injury for your hamster.
Although you can place a food dish in your hamster cage, it really isn't necessary. Hamsters love to forage for their food, so simply sprinkling their food throughout the bedding material in their cage will suit them just fine. In fact, if you do put food in a food dish they're likely to simply remove it and store it elsewhere anyway! As for water bottles, any water bottle designed for small animals should do just fine as long as the spout has a ball bearing at the end and a screw on top.
Consider adding extra toys to the cage to enrich your hamster's life, such as cardboard tubes, a wood gnaw, a sand box, a hamster house, etc. Your hamster will thank you for it!