The anatomy and physiology of freshwater and brackish water species differs from land animals in many respects. Freshwater fish and invertebrates have organs and systems not found in land animals. But, like other animals, freshwater species can have bacterial, viral, and fungal infections, as well as parasites. Learn about the normal body functions of freshwater fish and invertebrates, as well as the diseases that can affect them.
The nutritional needs of each individual freshwater species vary widely; each has its own special food preferences and requirements. While it may nearly be impossible to reproduce the exact diet that the inhabitants of your fresh or brackish water aquarium would eat in the wild, there are many types of foods and feeding methods available to the aquarist. Learn some nutrition basics as well as more detailed recommendations for specific species.