If it was affecting your anenomes, are you certain it was Velvet? Velvet only harms fish, leaves inverts alone.
Anyways, assuming it was velvet, the tank you treated should be Velvet free, and able to introduce fish.
Your hard inverts (crabs, snails, shrimp, hermits) however should be kept separate for no less than six weeks, as a stage of the velvets life cycle can attach onto the hard shells of those. After six weeks all traces of velvet should have starved to their well deserved death, and then the inverts will be safe to reintroduce into the main tank.