Which of the following may cause disease in a fish pond?

Poor management practices can cause disease in a fish pond. This can include overfeeding the fish, not maintaining good water quality, and not removing dead or sick fish from the pond. When the water quality deteriorates, harmful bacteria and parasites can grow and spread, causing disease in the fish. Overfeeding can also lead to excess waste and uneaten food in the pond, which can further degrade water quality and create a breeding ground for disease. Mixed stocking, liming, harvesting, and fertilization do not necessarily cause disease in a fish pond. Mixed stocking can actually be beneficial for a pond, as different species can complement each other and help control pests. Liming is used to adjust the pH level of the water and can improve water quality. Harvesting is necessary to maintain the right population density of fish in the pond. Fertilization is also important for promoting the growth of phytoplankton, which is a vital food source for fish. However, if these practices are not done correctly or in the right amounts, they could potentially lead to problems in the pond.