Aquaponics is a eco system in which a co existance of water animals and fish with off-shore plants. They tend to create a symbiotic cycle . In this type of eco system, generally the poops from fish  which plants intake a type of manure, thus help in growth and nourishment of the plants. By this, the contamination of water can be controlled and maintained to a very great extend.

The idea was pretty simple but requires lot of data/ results to validate it.