McALISTERVILLE - Tucked partially underground in Juniata County is a small research project investigating the productivity of aquaponics. Aquaponics is a term describing the marriage of aquaculture-culturing fish-with hydroponics-producing plants without soil. An abandoned concrete block trench silo was chosen as the location, to enable the use of geothermal moderation in both warm and cold weather. Deep ground temperatures in Central PA remain in the low 50s all year round, allowing the soil to be used as a heat source in the winter, and a cooling source in the summer. Two small polyethylene-covered greenhouses provide shelter for the fish and plants independently, allowing for differential control of the environment of each. The current research phase focuses on cold-water fish, rainbow trout, and cool-weather plants, lettuce and kitchen herbs, such as cilantro and parsley.