How do animals in freshwater bodies adapt to strong currents?

The life of animals in fresh water is different from the life of marine life. The river, as you know, always has a weak or strong current. As a result, river dwellers have to adapt to such conditions. Small fish have learned to hide under stones, where the current is not so strong. Also, small invertebrates hide under the stones, for example, mayfly larvae have a flattened body shape, they press against the stone and cling to it with small claws, resisting the flow. Some fish have a suction cup on their abdomen, with which they stick to the bottom. In many fish, a long streamlined body, together with developed muscles, allows them to resist a strong current for a long time.