By the way, get a new Swadloon. I assume you evolved it before Sewaddle got to level 31, at which point it gets Sticky Web, a great move. Only Sewaddle gets it, neither Swadloon nor Leavanny do.
Don't know if I'll even keep Swadloon. I just needed a bug type to off Espeon and Umbreon. Bug/Grass type has way too many weaknesses to be that effective. Dormammu the Braixen and Mr. Wayne the Swoobat should be useful for this gym.