The Assam’s fishery industry is under threat because of excessive use of urea. The was revealed by the Assam Apex Cooperative Fish Marketing and Processing Federation Limited (Fishfed) here recently after the state government imposed restrictions on imported fish. “A field survey revealed that many pisciculturists of the state use urea in an unscientific way. It is a challenge for the industry, which has bright prospects. In general, 3kg of urea should be used for pisciculture on one bigha of land. This is the norm in lower Assam but it is not followed by the farmers,” an extension officer of Fishfed said. Dipesh Debnath, a scientist with Central Inland Fisheries Research Institute, said, “Urea does not have any direct impact on fish. It is a fertiliser and a source of nitrogen. Therefore, in some aspects it is necessary for fish farming. But if it is used in excess, algae growth in a fishery will be higher, water quality will deteriorate and fish will die.” The Fishfed officer, who is mainly responsible for the development of local fish market in the state, said, “In Assam, fish farming is not organised. In the market, the size of fish is a big factor. However, most local farmers sell fish at advance fingerling stage. So the large fish market is dominated by imported fish.” Nitul Das, a fish farmer at Hajo, said, “In Assam, most pisciculturists lack awareness. It is one of the most profitable businesses and we have the resources but are not able to utilise it properly. The preservation of fish for a long time is also a challenge.” On Saturday, a group of officials from Andhra Pradesh collected samples of imported fish in Rangiya to verify the allegation of use of formalin. “The team collected nine samples and they will submit a report within Monday,” a source in the Assam fisheries department said. The team came after an investigation by Assam government detected formalin in imported fish. The Assam government on Tuesday banned the import of fish for 10 days.