That's just the way rodents are. Since it's amale his pee has a stronger smell. Carefresh is the best thing to use. Shredded paper is fine as long as it's just plan paper like say news paper or paper from your printer. Don't use anything shiney or colored like say K-mart's sale paper.
NEVERuse cedar or pine shavings as that bothers their breathing and can kill them. I have had rats and mice in the past and what hamsters can have is pretty much the same things. You didn't say what kind of food but lab blocks should be part of his diet so he doesn't get to fat. He can also have fresh fruits veggies 2 or 3 times a week too.
Any other questions feel free to connact me privately if you like.
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