API Tap Water Conditioner (1 oz, 12-pack display) – A concentrated aquarium water treatment that instantly neutralizes chlorine and chloramines and detoxifies heavy metals in tap water. Safe for all freshwater and saltwater fish, this conditioner makes tap water aquarium-safe in seconds. Just one teaspoon treats 10 gallons, protecting fish and beneficial bacteria by eliminating harmful chemicals and providing a healthy start for new water during water changes.