[pophammy]

Sometimes you can't train a hamster to use a potty. You can try and move all the dirty bedding into that potty, as this may encourage him to use it, but it doesn't always work.

Just one thing ~ by 'fluff' do you mean the cotton-wool type fluffy bedding? If so then you should not use this as it can tangle round limbs and block up pouches, causing death.