Freshwater aquariums are the most popular type of home fish tanks and aquariums as they are generally less expensive and easier to setup and maintain than saltwater aquariums. On average, a 30 gallon fresh water aquarium will cost around $300 to purchase and setup including the necessary components (gravel, filter, lighting, test kits and aquarium supplies such as food, nets and scrapers.) There is also a wide range of freshwater fish in the inexpensive price range of less than $10. It is certainly recommended for beginning aquarists to start with a freshwater aquarium.
Freshwater fish live in environments with a salinity of less than 0.05% such as lakes, ponds or streams. They differ physiologically from saltwater fish and are subdivided into cold freshwater and tropical freshwater fish. It is important to be aware of the kind of fresh water fish tank you intend to set up as this will affect the equipment you require and the kind of environment you need to maintain. You will need to research the kind of water parameters required by the species of freshwater aquarium fish you hope to keep. Obviously, the main difference between cold freshwater fish and tropical fish is the temperature of the water. Tropical fish tanks will therefore require a heater to be fitted.
The most common type of cold fresh water aquarium fish is the goldfish. Also popular is the Koi but they along with many other types are large and only suitable for ponds. Small to medium ones include some species of Barbs, Bloodfin Tetra, Buenos Aires Tetra, Croaking Tetra, Pearl Danio, Zebra Danio, Guppy and Weather Loach. One of the most popular tropical freshwater fish is the striking and easy to look after Betta. Other types which need to be carefully matched according to peaceful or aggressive temperaments include Rainbow fish, Platies, Mollies, Swordtails, Gouramis, Barbs, Tigerfish, Neon Tetras, Cichlids, Cory Cats and Loaches.
Once you have set up your freshwater aquarium with the gravel, equipment and décor, it is vital to ensure that tap water is treated with a dechlorinator to remove the chlorine which kills essential bacteria, before it is added to the aquarium. Before adding fresh water aquarium fish, the fish tank will go through a process of establishing beneficial bacterial colonies in the aquarium and in the filter media which get rid of waste and thereby maintain a healthy environment. During this time, which will take 2-8 weeks depending on the size of the aquarium, you need to keep monitoring the water parameters using aquarium test kits to ensure they are suitable for the fish you intend to have (temperature, pH, hardness, ammonia). When the nitrogen cycle is complete and you begin adding fish to your aquarium, you need to begin a maintenance schedule of daily checking fish and equipment as well as cleaning your tank every one to two weeks and performing larger water changes every month.