http://bulbapedia.bulbagarden.net/wiki/Move_Reminder
you need a supply of Heart Scales. the move reminder charges one per move remembered. if you're playing one of the 3ds games, they're pretty easy to acquire.
Running an Arcanine eugenics program. Would it kill you to have an HP IV of over 9? Please?
As an aside, who is going to adopt these hundreds of Growlithe pup rejects?