Early and basic systems combining fish and crops date back to Ancient Chinese techniques of raising fish among flooded rice paddies. Everything was harvested at once, and ducks were often used for both pest control and an additional source of fertilizer through their manure entering the water. Hydroponics was developed as a commercial agricultural system in 1938, while recirculating aquaculture reached a pinnacle of optimization for commercial use in the 1970s. Aquaponics were in use as early as 1969, but the recirculating systems most commonly used today weren't designed until the late 1970s through programs at the University of North Carolina and the University of the Virgin Islands. The three systems may have inspired each other and share many similarities, but they're also very different in terms of yield, cost, complexity and maintenance. Explore the differences between hydroponics, recirculating aquaculture and aquaponics to decide which type of business is right for you.