Giant barb

Giant barbs are usually seen in large pools along the edges of large rivers, but seasonally enter smaller canals, floodplains, and flooded forests. Young barbs are usually found in smaller tributaries and swamps, but can acclimate to living in ponds, canals, and swamps. The fish generally live in pairs. These are migratory fish, swimming to favorable areas for feeding and breeding in different parts of the year. These slow-moving fish subsist on algae, phytoplankton, and fruits of inundated terrestrial plants, rarely (if ever) feeding on active animals. In the lower Mekong basin, young giant barbs have been reported as occurring primarily in October. ==Physical characteristics==

The head is rather large for the body, with no barbels. It may reach (although this claimed maximum length needs confirmation) and weigh up to . Few large giant barbs are caught today. For example, no individual weighing more than has been caught in Cambodia since 1994. This fish is a tetraploid, meaning it has four of each chromosome (as opposed to diploid, the normal number in animals). ==Conservation==

Today, few barbs live to maturity. The main threats are habitat loss (e.g., pollution and dams) and overfishing. In 2005, the giant barb was successfully domesticated and reproduced for the first time at the Vietnam National Breeding Center for Southern Freshwater Aquaculture. In 2010, the Vietnam National Breeding Center released 50,000 young giant barbs into the Tien River in Dong Thap province Vietnam, but a later survey showed that only a few of them survived long enough to reach a weight of over one kilogram. In 2012, it was successfully reproduced in the Breeding Center of An Giang Province of Vietnam. == Cultivation ==

In recent years, raising giant barb has become common in Vietnam due to its high economic value. Two breeding centers in southern Vietnam offer about 1 million breeder giant barbs to farmers per year. When kept in floating cages in rivers, the fish grow fast and gain 7 kg to 9 kg per year. In ponds where the main diet is natural algae, the fish gain 2 to 5 kg per year. Usually, giant barbs are harvested after three years of cultivation when they weigh 6 to 10 kg, but some farmers keep raising their fish in ponds for more than seven years for them to reach 50 kg before harvesting. ==References==