I'd stay away from fish as they usually are not good for them. Walmart sells packs of 25 or 50 large night crawlers which is what I use for my pacman. I dip them in calcium power every other feeding. He loves them. Also I wouldn't give him a mouse that often, maybe once every two months or so because they're extremely fatty.
Ivoryreptiles suggest not to buy worms from walmart. she had tests run on them and there soil has chemical that are toxic to pacman frogs. a lil under 30 of her frogs died.