Choosing an Aquarium Light

For fish and live plants to thrive, aquariums require the right light conditions. A light can provide the day/night cycle that’s essential to natural life, and it’s a great way to enhance the colors of fish, plants and décor. In addition, the right lighting intensity is important to avoid unwanted algae growth.

Aquarium lighting comes in a wide variety of options to fit many types of aquariums. Some of the most popular are fluorescent, LED and halogen bulbs. Fluorescent lamps are a great choice for freshwater aquariums because they are relatively inexpensive and emit the most natural-looking light, especially when matched with a reflector.

Halogen bulbs are a great option for reef tanks because they produce the brightest, whitest light and replicate the spectral characteristics of natural sunlight. These lights are a bit more expensive than standard fluorescents but offer excellent longevity.

A great alternative to halogen is metal halide lighting. These lights are a favorite among many reef aquarists because they recreate the shimmering effect of tropical sunlight over a coral reef. These lights are also available in a wide variety of spectral settings from 5000K to 20000K to accommodate a range of corals. However, they can use up to 150 watts and produce copious amounts of heat so they are not recommended for beginner aquariums.

In general, it’s a good idea to stick with the light level your fish and plants are accustomed to in their native habitats when choosing an aquarium light. Too little light can cause stress, while too much can promote undesirable algae growth.

It’s also important to consider your water depth when selecting a fixture. Certain wavelengths (particularly blue) penetrate deeper into the water than others, which is helpful for plants that need to absorb light for photosynthesis.

The type of light you choose should also depend on your tank setup. For example, a glass-topped aquarium requires a different light than an acrylic tank since it lets more UV radiation through. Most aquariums with live plants are better served by an LED fixture that produces more intense light, which is also more energy efficient than a halogen.

Expert note: When shopping for a new light, it’s a good idea to familiarize yourself with the Kelvin rating of each bulb, which indicates the color spectrum and tone it gives off. A low Kelvin rating produces warmer colors such as reds and oranges, while a high rating produces cooler, bluish tones.

A simple timer is a great way to regulate the light period of your aquarium and keep it consistent with your local weather patterns. In addition, the correct timer can prevent over-exposure to light which can cause unwanted algae growth in non-planted aquariums.

Smart aquarium lights such as the Aqueon OptiBright Smart LED Light can be controlled directly from the app on your smartphone, making it easy to set up a realistic day/night cycle and even add weather events such as rainstorms or moonlighting for more natural effect. They also consume less electricity than other types of lighting, produce significantly less heat and last longer than conventional bulbs.