Shallow lakes can be either clear with plants or murky with algae. To keep lakes clear, we need to control the amount of phosphorus coming in and how long the water stays. If we have too much phosphorus for too long, the lake will turn murky. But if we reduce the water's stay time, the lake can stay clear with plants. By managing phosphorus levels and water time, we can keep lakes clear for a long time. This study helps us understand how to maintain a healthy lake ecosystem.