If you want a saltwater aquarium, there's a lot of planning to do. Those who skip this most important first step are usually disappointed in what they wind up with, but can't figure out where they went wrong. The place to get started is with the right tank.
Choosing a Tank
Two basic varieties are available:
Which one is right for you is merely a matter of personal preference and wallet size (glass is usually cheaper).
Try to buy the largest tank that is practical. The bigger the tank, the easier it is to maintain water quality, stabilize the system, and stock fish – plus a larger tank allows space for the fish to cruise around. A 40-gallon tank is a good beginning, although if you can handle the extra volume, go for more. If you plan on going for a single-species tank, then a smaller tank will do, but smaller than a 20-gallon tank is not advised because it becomes more difficult to maintain water quality. Another consideration is whether your pumps and filters will be inside or outside of the tank. Obviously, internal systems will take up space in the aquarium, leaving less room for fish and decorations.
Before setting up the tank, clean it with the appropriate materials and tools. A thorough rinsing of a new tank with tap water and a soft, non-abrasive cloth should do. Never ever use ammonia-based products, soaps or detergents around the system. These chemicals are extremely toxic to aquatic life, even in very small amounts and can also erode the silicone and plastic that hold the tank together and keep it from leaking. Many sponges, paper towels and cloth towels can abrade acrylic, so check the manufacturer's instructions for their suggestions.
Where to Place Your Tank
Decorating Your Tank
Saltwater has the ability to dissolve metals and some artificial colors that would, in a freshwater set-up, remain unaffected. Don't use any metals in a saltwater tank unless they were specifically manufactured for use in such a system. If you want to use artificial plants or other suspiciously colorful tank accessories, make sure that they are also safe to use in a marine system.
The best way to avoid problems with your décor is just to "go natural." Using coral rock or dolomite or aragonite gravel is highly recommended since it will help buffer the pH in your tank, giving you some advantage in maintaining the system. Some aquarists, however, point out that gravel is difficult to clean, because it can trap waste and uneaten food and can thus deteriorate water quality instead of improving it.