THE NUTRIENT CONTENT AND THE RELEASE OF NUTRIENTS FROM FISH FOOD AND FECES

The fish food and faeces were fractioned into the different components of phosphorus and nitrogen. There was a rapid release of phosphorus f rom the fish food and faeces and a decrease thereafter whereas ammoniu m release was slow at first with the rate increasing with time. Both t emperature and pH affected the release of nutrients from fish food and faeces. The release of phosphorus and nitrogen was higher at higher t emperatures. The maximum release of phosphorus was at pH 4.0 whereas n itrogen release was maximum at neutral (7.0) to alkaline (10.0) media.