Glossary of Aquarium Lighting Terms

2G11 - 4 pin straight configuration for compact fluorescents

Actinic - Blue spectrum of light that peaks in the 420 nanometers range

ANSI - American National standards Institute

Arc Tube - Sealed tube within a metal halide bulb where light is generated

Ballast - A coil that regulates the power going to the bulb

BU - Base up. Refers to the burning position of a metal halide

CRI - Color Rendering Index, Measures the color rendering ability in comparision to natural sunlight

DE - Double-ended, Refers to HQI metal halides

E39 - Standard mogul base

GX23 - 2 pin configuration for compact fluorescents

GY10Q - 4 pin square configuration for compact fluorescent lamps

HID - High intensity discharge

HO - High output, usually refers to fluorescent lamps

HPS - High Pressure Sodium

HQI - Commonly refered to as double-ended metal halide bulbs

Ignitor - Generates pulses of voltageto start a lamp

Initial Lumens - Light output of a bulb at 100 hours or operation

Lumen - Measures light output

Kelvin - Scale used to measure the color of light

Medium Base - E26 base, similar to household incandescents

MH - Metal halide

MV - Mercury vapor

Mogul - E39 base, standard base for metal halides

Nanometers - Used to measure wavelengths in the electromagnetic spectrum

NO - Normal output, standard output fluorescent lamp

PC - Power compact, same as compact fluorescent

Probe Start - Metal halide lamp that uses a starting electrode

Pulse Start - Metal halide lamp that uses an igniter in conjunction to the ballast to start the bulb

SE - Single-Ended

U - Universal, refers to the burning position of a metal halide

VHO - Very high output