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Lesson Overview
  • 120 Minutes
  • 6th - 8th Grade
  • State Standards:
    6-8.RST.4 6-8.RST.4 6-8.WHST.6

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Materials List

-Aquaponics System
-What Do Plants Need to Grow? worksheet
-Exploring Fish Needs worksheet
Meeting the Needs worksheet
Creating a Nitrogen Cycle Collage worksheet

Exploring the Nitrogen Cycle through Aquaponics

Categories: Easy Do-at-Home Activity , Agriculture , Plants

Students investigate the growing of food through an aquaponics system and the symbiotic existence between plants and fish.

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As the global population grows, simultaneously the amount of available farmland decreases. The challenge of feeding more individuals on less land becomes very real and relevant. Aquaponics presents one possible solution as it incorporates both plants and animals into one system and leaves little waste. There are two basic ideas coming together for aquaponics—growing plants without soil and raising fish. This differs from hydroponics which does not include fish. In an aquaponics system, fish are fed and then excrete solid waste that is converted to ammonia by bacteria in the system. Ammonia is toxic to fish and a build up in the tank may cause the fish to die. Beneficial nitrifying bacteria convert the ammonia to less toxic nitrate, which is readily absorbed by the plants growing in the grow tray. By cycling the ammonia and nitrate filled water to the plants, the plants remove these forms of the nitrogen from the water, and use them to grow. The water then filters down through the grow tray and returns to the tank, giving the fish fresh clean water to live in. Both the needs of the plants and fish work together in an aquaponics system, providing larger world applications of how this industry will only grow in the future. Aquaponics is one sustainable method of food production. Aquaponics systems are environmentally responsible with lower water usage and relatively low power usage.