Freshwater fish are perhaps the easiest fish to care for in comparison to saltwater species because they are usually hardier fish. A basic aquarium set up will be required. You will need a tank, some rocks or substrate to line bottom of the tank. You will also need a filter, and some lighting. When choosing fish, it is imperative to make sure the fish are compatible. Not only do they need to be compatible for water temperature and P.H., but they also should have similar food requirements. Try to keep the fish relatively the same size. It has been said that if a fish is small enough to fit in another fishes mouth, that is usually where it ends up. So don’t be discouraged if this happens. Even fish that have been housed together for several months have been known to disappear on occasion.