Sounds good, but the it doesnt stop there. Regardless if you've filteres out chlorimine, ammonia, copper, etc.. The water hardness of your tap water stays the same. I havent really looked into filters for tap water before. Try testing the water after its been ran through the filter and let us know how it goes..
Once the activated carbon and resins are used up, you will need to purchase a replacement filter cartridge ($17.99). So you're better off sticking to the water conditioner. Besides that, you will need to reconstitute it with a pH buffer and add trace elements back to the treated water to make it fish safe.