Farmers use fertilizers on their farms to help increase the growth of their crops.
Then when the rain comes, the wet runny soil along with fertilizer causes a runoff.
The runoff of soil and fertilizer reaches a lake. This causes the rapid growth of algae at the bottom of the lake. These algae block the sunlight from the plants underneath them and stop in from reaching the plants to aid in photosynthesis.
The plants then die due to lack of growth and sink to the bottom where bacteria begins to decompose them.
In loving memory of Larry the plant.
When all the oxygen is used to decompose, the water no longer has oxygen.
The fish in the lake die due to lack of oxygen in the water.