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Marketplace where fish seed is sold Farmers performing rigorous aeration by hand for the transportation of the seed from the pond to market. These workers are called bhars and will carry two pots full of fingerlings on their shoulders with the aid of a single bamboo stick. After the 60 day rearing period the farmers end with around two or three lakh (a Vedic unit of measurement meaning 100,000) of seed from four lakh of spawn and by selling two to three lakh of seed they earn around 75-80 thousand rupees in each cycle and from this gross return the farmer makes a profit of 45-50 thousand rupees in each seed nursing cycle. creation of a bamboo fence and dumping the vegetation in such enclosures. Adding manure to the vegetation pit should stimulates the process of composting in aquatic environment and increase productivity. IMPROVING THE PH OF THE PONDS Udaipur sites are reported to have acidic soils. The pH of water is an important criterion in producing an adequate amount of natural food in the water through effective release of nutrients for the production of such organisms. Application of lime is essential to rectify the pH of water. In general, 200-500 kg/ha can be applied to all ponds, irrespective of the pH status. In ponds with low pH, higher level application would be necessary. In rural areas, availability of lime may be a constraint and in place of lime, ash produced at home by burning firewood or various other sources can also be used. Ash produced from Banana is reported to be having very good impact in improving pH of water. Green water is essential for fish growth APPLICATION OF MANURE AND FERTILIZERS Farmers generally have cattle and cattle manure is popularly used in fish culture, though its efficacy is far lower compared to pig or poultry waste. The amount of manure being applied by Udaipur farmers could be as much as 30 tonnes per hectare per year. In addition to organic manures, chemical fertilizers like nitrogen and phosphorous fertilizers are used. SUPPLEMENTARY FEED Ash is used to control water pH levels KEEPING THE WATER GREEN Green water is essential to increase the growth of fish based on the natural food produced in the pond. Most carp depend upon the natural food produced in the pond and this is eaten by the fish through the filtration process. The northeast has plenty of greenery and vegetation that is rich in nitrogen, particularly Eupatorium spp. All such plants are composted in various corners of ponds by the When the fish are stocked at a higher density they are provided with supplementary feed. Rice bran is commonly used as supplementary feed combined with oil cakes. In the eastern part of the region, mustard cake is the most commonly available. However, the cost is the key factor in feeding fish and farmers regulate the level of oil cake in such a way that best results are obtained without wastage. The state of Tripura, in which this case study at Udiapur was conducted, has more than 90 percent of the population that consumes fish and while the state government is aiming to supply at least 12 kilogrammes per person per year, the actual requirement for fish is certainly more. Seed nursing does not require large water bodies; and seed can be raised in small water bodies. Culturing fish seed could provide a better option for the fish farmers of northeastern India as they need not spend an entire year to gain a harvest. In just 12 months farmers can perform three to four harvests and make money in a short period of time. Seed nursing could ultimately solve the problem of seed availability in the market of Northeastern India and lead to an increase the overall fish production. JULY/AUGUST 2013 ■ NZ AQUACULTURE ■ 7