In the pac man care sheet it says that juveniles can be fed 5-7 times a week. Earthworms will not make him impacted so dont worry about that. I do want to add one more thing- When I make my dechlorinated water I let the jugs sit out overnight to give the chlorine time to leach out. I make several at a time so I always have dechlorinated water on hand. I hope this helps!