Merlin had that in his adolescence, and pretty severely as well. Our vet suggested we switch him to metal food and water bowls and run them through the dishwasher daily for water and after every meal for food bowls. He suggested non-alcohol hpyo-allergenic baby wipes for frequent clean-ups after meals and also the benzoyl peroxide cream twice a day. It will clear up, then flare up, and eventually clear up altogether on it's own as they get older, but it is unsightly and messy until then. I actually have been waiting fo it to show up on Strider, but knock on wood, it hasn't yet.
Good luck!
Stella