Q.Group of students visited a fish farm where they found Catla, Rohu, Cirhina mrigala cultured in the same pond. Name the type of fish farming observed by the students. Mention any two advantages of such farming system.

Aquaculture is the farming of aquatic organisms — fish, molluscs, crustaceans and aquatic plants — classified by water source into freshwater aquaculture (inland rivers, lakes, ponds and reservoirs, salinity below 5 ppt), brackish water aquaculture (estuaries, backwaters and coastal lagoons, salinity 0.5–30 ppt) and marine water aquaculture/mariculture (India's roughly 5,600 km coastline, salinity 30–35 ppt), with a further metahaline category (36–40 ppt) exemplified by the brine shrimp Artemia salina. Fish culture (pisciculture) is its largest component: a good cultivable fish must grow fast, accept supplementary feed, resist disease, coexist in polyculture and convert feed efficiently, which is why major carps (Catla, Labeo, Cirrhinus) dominate Indian practice. Managing a fish farm moves stock through a chain of specialised ponds — breeding ponds (using natural bundh breeding or induced breeding via artificial fertilization or hypophysation), hatching pits, nursery ponds, rearing ponds and stocking ponds — bef …