High flow float valve for maintaining the water levels in troughs, tanks, and other holding vessels. Designed for above or below water mounting, and is equipped with an adjustable extension arm for varying water levels. Patented 1/4 turn removable base for ease of servicing, cleaning, and accessing the internal filter. Compact, non-corrosive, and robust. Operates from 5 - 100 psi with a full flow design that resists valve hammering in turbulent applications.