Ornamental fish keeping is becoming popular as a relaxing and stress relieving hobby, throughout the world. The growing interest in aquarium fishes has resulted steady increase in aquarium fish trade, globally. The culture of ornamental fish envisages not only the production but also improvement of their colour and aesthetic beauty to suit the requirement of consumers. The colouration in ornamental fishes is due to the presence of colour pigments known as carotenoids. Xiphophorus helleri (red variety) is one of the most commercially important ornamental fish more frequently seen in aquarium...

A rapid expansion of fisheries is demanding an adequate supply of efficient, nutritious and inexpensive fish feed, because feed contributes highly to the cost of fish production. Feeds form an essential component of successful fish farming. Feed costs can account for up to 70% of the total operating cost in aquaculture. Therefore there is a urgent need to reduce feed cost significantly in order to increase the profit margin. Waste generation is major problems in vegetable as well as fish processing. The volumes of waste generated as well as resultant environmental impacts necessitate the...