Welcome your fishy friends home the right way with Dr. Tim’s Aquatics Saltwater One and Only Cleaner. This cleaner contains live beneficial bacteria which work to remove toxic ammonia and nitrite from your saltwater tank. It’s designed to prevent new tank syndrome by establishing a biological filter in your fish’s new home. This formula is great to use with a new tank or after treating or changing your finned friends’ water. It contains no sulfur or bad odors and it’s designed so you can safely add your fish back to the tank immediately. Swim easy， little pals!