Oligotrophic lakes, ponds, or rivers have very low levels of nutrients in the water. Low nutrient levels results in low levels of plant, algae, and animal growth. They usually have very clear water, little weed or plant growth, and not many fish or other animals. Also, because there is not as much plant, algae, and animal growth, the bottoms of oligotrophic lakes and streams are usually rocky or sandy, with little organic matter to make them mucky.