The most colorful fish are found in marine habitats. A marine or saltwater aquarium is desired by many aquarists. A marine aquarium is more difficult to maintain than a freshwater aquarium. Salt, being a corrosive agent, can be damaging to a lot of aquarium equipment. Constant monitoring of the cleanliness of the aquarium, inside and out, is important to the overall appearance of the area. A freshwater system, on the other hand, is much easier to maintain. A weekly cleaning will usually suffice to keep the appearance looking good. There are many freshwater fish that are just as colorful as marine fish and will do very well in a home aquarium. When setting up an aquarium for the first time, a freshwater aquarium is suggested.