Hands-on education al experiences help students relate to scientific concepts in more tangible and effective ways. When teaching about the complex relationships that exist in aquatic ecosystems; educators can implement the culture of fish and plants in an aquaponics system to reinforce classroom curriculums and more effectively reach learning targets. Utilizing aquaponics as an applied , project based investigation (PBI) experience promotes student comprehension of broad scientific concepts, including those defined in the Next Generation Science Standards (NGSS). Aquaponics project-based investigations (APBI) teach students about the importance of cycling nitrifying bacteria, the carrying capacity of an ecosystem, and the complexities of aquatic animal husbandry in relation to science, technology engineering and math (STEM) concepts. This intervention shows how APBI promotes student development of interdisciplinary connections and contextualized problem solving.
Recirculating aquaponics system components , fish, and plants were delivered by Kentucky State University's Aquaculture STEM Extension staff to four rural high schools located in multiple districts in central Kentucky, USA . The participating classes were biolo gy or agriculture-based and contained an average of 30 students each . Students engineered the system design and collected data including water quality parameters , feeding rates, and biomass of the fish and plants throughout the 12-week unit . Two separate APBI trials were investigated: 1) Eight week large system , whole-c lass investigation; 2) Four week small system, student group investigation. T he APBI central driving research question throughout this project was: How does nutrient input affect the carrying capacity of our aquaponics eco system? This question wa s used as a guide for the intervention design and it facilitated the learning objectives within the benchmark lessons . Students observed how feeding rate (nutrient input) can affect the water quality and productivity of their living systems. Students were also able to discover that aquatic systems have limits in terms of nutrient input and when the carrying capacity of a system is met, harm can come from excessive waste accumulation. These factors were emphasized when the scale of the system was reduced for the small tank investigation and the students had to accommodate for reduced water volume and the increased rate of waste toxicity.
The inconstant nature of an aquaponics system allows students to better understand the multifaceted interactions that naturally occur between the water, plants, fish and bacteria. This APBI encouraged students to use analytical reasoning skills in conjunction with STEM based problem-solving to ensure the health and success of their aquatic ecosystem .