Reef Aquarium Light Basic Information

The following information on reef aquarium light basics will provide you with the knowlege you need to make an educated choice on what type of lighting you need. The following are terms you need to learn.

This type of bulb ulluminates using the blue spectrum. Actinics will penetrate the deepest of all the the spectrums. Most setups have at least one actinic bulb.

Actinics promotes the growth of Zoaxanthellae algae, essential for the growth and well-being of all photosynthetic corals and invertebrates.

The ballast is the part of the system used to start the bulb burning and keeps it running within the bulbs parameters. The newer electronic start ballasts are energy efficient and will save you a bit on your energy bills.

The spectrum or temperature is measured in degrees in the Kelvin scale. Sunlight at high noon on a reef is 5500K and is usually refered to as full spectrum. This means it contains all the colors of the spectrum, from yellow all the way to violet. Red is lower on the Kelvin scale and color temperature, while blue is higher on the Kelvin scale and has a higher color temperature.

Intensity is measured in 2 ways. Lux and Watts. We will only concentrate on the Watts measurement. Watts is measured at the source of the bulb. The higher the watts, the more intense the bulb becomes. It also requires more energy to produce higher wattage.

Par is a little hard to explain but here goes. Par is basically the color/temp range that the corals can use for photosynthesis. It's not really intensity but more a measure of light temp that corals and other things can actually use. You need a light with good PAR values if you are planning on keeping sps corals. The higher the par, the deeper the light will penetrate.