... easy to install, no need human source 8020 Venturi fertilizer,Size: 2"low price, easy to install, no ... of Venturi.2, And connect the venturi fertilizer with the water supply pipe.3, When in use, turn ... the valve,4, this pressure diference makes the water flow through the pipe of venturi automatically, then ... be a vacuum after the water,5, the vacuum will suck the fertilizer liquid into the pipe network. ...