Last week, several students from the John M. Barry Boys & Girls Club visited Elmwood Farm in Hopkinton to learn about its aquaponics and energy sustainability.  The students learned how aquaponics combines aquaculture (raising fish in tanks) with hydroponics (growing plants in water) in a symbiotic balance as excrement from fish becomes nutrients for plants, which filter the fish environment.  They also earned about Elmwood Farm’s total solar energy self-sufficiency.  They met cows and sheep and participated in farming operations — feeding chickens, collecting eggs, planting and harvesting vegetables.  The Club’s Education Director, Tamara Brogan, arranged the after-school field trip.