Fish farming is the principal form of aquaculture, while other methods may fall under mariculture. Fish farming involves raising fish commercially in tanks or enclosures, usually for food. A facility that releases young (juvenile) fish into the wild for recreational fishing or to supplement a species' natural numbers is generally referred to as a fish hatchery. Worldwide, the most important fish species used in fish farming are carp, salmon, tilapia and catfish.

 Fish keeping is today the world’s most popular hobby after photography and ornamental fish are the most popular pets in the world. Keeping ornamental fish and its propagation provides not only aesthetic pleasure but also an excellent financial opening for providing employment opportunities to many especially for unemployed youth, women, and others. Ornamental fisheries provide for a major diversification of aquaculture practices. The total world trade of ornamental fish including accessories is said to be worth about US$14 billion.

Compared to other Asian countries, the Indian ornamental fish sector is very negligible but vibrant, with potential for tremendous growth and large scale gainful employment generation. Indian production is over 100 million fish from 1750 units (170 ha) which is very low compared to Singapore and Malaysia. Currently India produces about 124 varieties of fish under the major groups and exports increased from US $ 0.8 million in 2000 to US $ 1.7 million in 2008. There are more than 1.5 million people keeping ornamental fish in their houses in the country. More than 100 species are traded in domestic market among which 35-40 species of fresh water fish dominate the market. Cities like Kolkata, Chennai and Mumbai are the key producing state for production of ornamental fishes and trade.

Many other states of India now showing interest and slowly they are popularizing ornamental fish farming by the help of many Central Institutes like CIFA, CIFE and other Fisheries colleges located in India through training and demonstration.  The Indian Council of Agricultural Research (ICAR) has incorporated the production of quality ornamental fishes, both freshwater and marine, through National Seed Project. Through NAIP livelihood projects hatcheries are being established for sustainable production of ornamental fish among tribal areas for livelihood securit