Each environment has its own unique criterion, including ongoing costs, everyday maintenance, and related fish care requirements. Sure, a saltwater (SW) tank requires considerably more work and attention, but it's hard to beat the satisfaction of knowing that you created a unique environment for warm water fish that few aquarists enjoy. Obviously, many will argue that a freshwater (FW) system has its own merits. At the end of the day, personal preference tells you which setup is right for you. Of course, practically speaking, so does cost. But if the commitment to creating and maintaining either type of system isn't daunting enough to keep you away, you'll be rewarded by your efforts from the moment your fish are introduced to your tank Read this book that will help you decide.