DrTim's Aquatics One and Only Freshwater (DrTim's Aquatics One and Only Freshwater, 2oz)

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 oz size for freshwater aquaria up to 30 gallons. One and Only has no sulfur or other offensive odors. Made by the recognized expert in aquarium nitrification and microbiology.