GELCOAT A colored,
polyester-resin material applied to the surface of a molded part. The gelcoat
hardens to a smooth, durable form and becomes an integral part of the laminate.
Fiberglass pools and spas have gelcoat finishes.
GPD An abbreviation for
gallons per day.
GPH An abbreviation for
gallons per hour.
GPM An abbreviation for
gallons per minute.
GRAB RAIL Also called hand
rail - A tubular steel or plastic device that can be gripped by swimmers or
bathers for the purpose of steadying themselves. Usually located near the steps
in the pool.
A condition caused by too much copper in the pool water. Green hair is not
caused by chlorine. The copper may get into the water by the bad practice of
placing trichlor tabs in the skimmer. This acidic product will cause low-pH
water, which in turn will dissolve metals in the equipment. The dissolved metal
(usually copper) then stains hair, fingernails and, eventually, pool walls. It
can also be caused by keeping the pH too low or misusing acid.
INTERRUPTER Also called a GFI - A device intended to protect people. It
interrupts (de-energizes) the electrical circuit whenever it detects the
presence of excess electrical current going to ground (usually 1/40th of a
second and 5/1000th of an ampere).
GUNITE A mixture of cement
and sand sprayed onto contoured and supported surfaces to build a pool. Gunite
is mixed and pumped to the site dry, and water is added at the point of
application. Plaster is usually applied over the gunite.
GUTTER An overflow trough
at the edge of the pool through which floating debris, oil and other
"lighter-than-water" things flow. Pools with gutters usually do not have