Proceedings of the Third World Fisheries Congress: Feeding the World with Fish in the Next Millenium—The Balance between Production and Environment
Analysis of Diseases of Aquarium Fish Cultivated in Natural Seawater
Yong Jiang, Jun Xie, Yan Wu, Qi Zhuo
Fish diseases are mainly caused by stress or poor water quality (Browdy 1993; Burgess and Matthews 1995). The most common disease is marine white spot (Burgess 1995). Much research has been conducted on pathogens in aquarium fish (Herwig 1978; Violetta 1980), but few studies emphasize on the relationship between pathogens and water quality. In this paper, we examine the relationship between pathogens of marine white spot and parameters of water quality in the Shenzhen Sea World Aquarium.
Shenzhen Sea World Aquarium is located at Dapeng Bay, in which fish are cultivated in natural seawater. Totally, it houses more than 500 species and 4,000 fish. Since the opening of the aquarium, some fish have suffered from disease. Diseased fish were examined under a microscope. Ammonia, dissolved oxygen (DO), nitrites, pH, nitrates, and phosphorus as phosphate were measured regularly.
The gray correlativity analysis was applied to study the effect of dominant factors on fish diseases. The distinguishing coefficient is 0.5. First, the data were standardized by average value. The coefficient of variation indicates the change of water quality index and is calculated as follows.