Bedding Depth
Hamsters will need lots of attention in order to not become lonely or depressed. They also need attention in order to be healthy. They will need fresh water, food, and playtime daily. They will need toys and other items moved or treats hidden in bedding as variety weekly. And they will need a clean habitat monthly.
Attention
Hamsters will need a sand bath to dig and roll in. You can purchase a bag of sand at most any gardening store. You can boil or bake the sand to sterilize it. It must be baked or boiled in order to remove any germs or bacteria and even bugs. You might also find that your pet store sells bathing sand usually for chinchillas. You can also use this. Do not use dust or water to bathe your hamster.
Hamsters can live in temperatures around 65-70 degrees fahrenheit or 18- 21 degrees celsius. If you live in a very hot area and cannot keep the temperature cool enough, you can place clean tiles on the floor of the cage (no bedding under), the tiles must be smooth and not sharp enough to cut or scratch the hamster. You can also put ice cubes in their water. If you live in an area where it's very cold very often, and you cannot control the temperature, you can add more bedding, place bits of ripped up tissue (No lotion or medicine, only plain tissue) in the cage so your hamster can make a cozy nest.
In the wild, hamsters would dig burrows underground. This means you will have to provide plenty of substrate. You need at least 3 inches of bedding, but you can add more if needed.