Best thing I ever found for fleas is the vacuum cleaner with disposable bag.

Looooooove my vacuum cleaner.

We had a massive flea invasion from the carpet when we moved into our new apartment. I vacuumed every day, bathed the dog a couple times in regular shampoo, sprayed him with cedar oil doggie fur conditioner, and problem was solved within a couple months.

Carpet is just yucky. So many yucky things lurk in carpet.