As the subject says, has anyone built one yet? Its springtime in Swazi and my lawn needs fert urgently, thus i would like to fertigate somy liquid fertilizer , as its the easiest obtainable to me. The fertilizer is fairly corrosive so i would like to inject it between my hoosepipe and mobile impact sprinkler so that the fertilizer doesnt touch my underground piping. Any pointers would be greatly appreciated