Dr Tim's Aquatics One & Only Live Nitrifying Bacteria - Freshwater

One and Only Live Nitrifying Bacteria removes toxic ammonia and nitrite, instantly working to prevent new tank syndrome by establishing a biological filter in your newly set-up aquarium. Use when setting up a new tank, after a disease treatment or water changes. 2 ounce size for freshwater aquaria up to 30 gallons. One and Only has no sulfur or other offensive odors.