To be honest. I don’t know. If I was a store and you wanted to return an infested anything I think I would hesitant. But who knows. Call them. Of course there is a third option. Keep the rock and put it aside. Get new dry rock. And use that. While your in that down time waiting forever for the tank to cycle. Treat the rock as suggested by Diana and put it away. There will be a day when you will want to upgrade your tank. Most people, including this guy. dreams of a mega system (of course that means different things to different people) and you will have a few nice pieces stored away that can be cycled before you even have water in the tank.