I use well water and RO water to do water changes in my three fish aquariums. I also use a water conditioner in the well water before adding it to the tanks to make certain that it is free of heavy metals and other dangerous chemicals. NovAqua+ Plus Water Conditioner by Kordon is the product that I am presently using. I have a 16 fl oz bottle of it, and one teaspoon per 10 gallons of water is all it takes to make the water safe for my fishy friends.
NovAqua+ Plus contains echinacea, vitamins and anti-virus protection. It detoxifies tap water and removes chlorine and toxic metals. It also breaks down chloramines in the water.
NovAqua+ Plus also adds protective skin slime for the fish, aids in the immune health of the fish, has natural electrolytes and vitamins, and is an organic virus and harmful bacteria inhibitor. This stuff does a lot in helping to keep pet fish healthy and happy. It is non-toxic to humans, pets and aquatic life, and when added to the water, it will not affect the beneficial bacteria in the tank. NovAqua+ Plus also contains no phosphates and is for fresh and saltwater tanks.
I have used other conditioners before trying NovAqua+ Plus and find it to be as effective as anything else I've used. And one 16 oz bottle will last quite a while.
If you are looking for a water conditioner for fish aquariums, you may want to give NovAqua+ Plus a try.