When fish farms are built along the coast, waste can go into the surrounding water. This can include uneaten food, feces, and other organic matter. This can pollute the water and harm the environment, including damaging coral reefs and killing fish.

To reduce pollution from fish farms, a number of measures can be taken, including:

- Using a closed containment system, which prevents waste from escaping into the environment

- Using filters and other treatment systems to remove waste from the water

- Regularly cleaning the fish farm and removing waste

- Using feed that is specifically designed to be easily digested and produce less waste