Term
	Definition
GALVANIC ACTION	Creation of an electrical current by electrochemical action.
GLAUCONITE SAND	A mineral which is frequently used in depth filters.
GPD	Gallons per day. A flow rate measurement
GPG	Grains per gallon. Equivalent to 17.1 milligrams/liter of calcium carbonate.
GPH	Gallons per Hour flow rate measurement
GPM	Gallons Per Minute / Rated capacity of a pump
GREY WATER	Wastewater from household baths and washing machines that is sometimes recycled especially for use in gardening or for flushing toilets.
GUTTER FITTING (GUTTER DRAIN)	A drainage fitting used in the overflow gutter.