The tank filters are only there to provide water movement and remove ammonia / nitrites. It won't have any effect on the concentrations of chlorine, chloramine, or heavy metals that tap water contains and are all deadly to fish. Additives such as Prime or API Stresscoat will work well to remove them.
Try taking a look at this link. It has a lot of useful information for fish keeping.
Guide to Starting a Freshwater Aquarium - Aquarium Advice
Also, in order to keep your fish healthy it's best to do a weekly 50% water change to keep the contaminants from his waste to a minimum.