The Easiest, Fastest and Cheapest way to achieve Crystal Clear Water. Every fish keepers first priority is the health and happiness of their fish. But their second is having a beautiful looking fish tank! Ever wondered how some aquariums have crystal clear water but you just can't get yours that clear? Well it's pretty simple to achieve! With a few tweaks to some errors that most beginners make and a few implementations of effective tools you can easily have crystal clear aquarium water.