Aquarium Light Bulbs

One of the most important features of a correctly equipped aquarium is proper lighting. Not only do the proper aquarium light bulbs illuminate, they also become a vital part of this miniature ecosystem. Choosing the proper light bulb can make the difference between a healthy, flourishing aquarium and one that struggles to stay alive.

What Does an Aquarium Light Bulb Do?

The most obvious purpose of an aquarium lighting system is to make plants and animals more visible so that they can be seen and enjoyed. Beyond that, though, the lights play a key role in maintaining the ecosystem inside the tank. Since many plants and animals rely on the sun to fuel photosynthesis, a proper light source is essential. Lighting also plays a role in fish health and behavior. In many cases, the aquarium bulbs provide the majority of the light the aquarium receives. In some cases, they may be the only source of light, so proper bulb selection can vary depending on the surroundings and the aquarium's inhabitants.

Choosing an Aquarium Lighting System

When choosing an aquarium lighting system, there are a wide range of factors and type of systems to select from. However, the choice of lighting system can be simplified by considering three main factors:

  • The type of light needed by the aquarium. Setups with plants will have different needs than fish only aquariums. Saltwater tanks will also differ from freshwater tanks.
  • The amount of light needed in the aquarium. Different size tanks will need different amounts of light. The amount of light needed also depends on the inhabitants and whether it is a fresh or saltwater aquarium.
  • The style of light desired. There are three main categories of aquarium lights: normal fluorescent lights, compact fluorescents and high intensity metal halide bulbs. Different styles of lights have different energy requirements and other characteristics that may make one preferable over another.

Types of Aquarium Lighting

Different aquariums have different lighting requirements. There are a diverse variety of aquarium bulbs and lighting systems, which allows the hobbyist to select the right bulbs for their particular setup. Some of the different types of bulbs available include:

  • Actinic Bulbs
  • White Actinic or 50/50 Bulbs
  • Color Enhancing Bulbs
  • High Intensity Bulbs
  • Plant Bulbs
  • Daylight or Full Spectrum Bulbs

Actinic Bulbs

Since the light emitted by these bulbs is mostly blue, they are well suited to aquariums that attempt to mimic conditions found in deeper ocean waters. They emit the type of light that is needed for the wellbeing of photosynthetic coral to grow and thrive. They are best suited for a reef aquarium.

White Actinic or 50/50 Bulbs

These bulbs produce a mix of light. They emit blue light similar to actinic bulbs along with white light that is more suited to the human eye. This blend of light helps photosynthetic coral to grow while still providing illumination that is pleasing to people. They are best suited for a reef aquarium.

Color Enhancing Bulbs

These lights feature the warmer colors of the visible spectrum, the reds, yellows and oranges. They help to enhance and augment the colors that are normally filtered out by water, so the colors and beauty of the fish show at their best. Since they don't provide all of the wavelengths needed for photosynthesis, these are suitable for fish only aquariums, either fresh or saltwater.

High Intensity Bulbs

These are bright lights that emit a high color temperature white light. They are rated by color temperature, or Kelvins (K), and usually can be found in a range from 10,000K to 20,000K. The higher the Kelvins, the cooler the light color will appear. A 20,000K bulb will produce a cool light that simulates deeper ocean conditions. They are usually used along actinic bulbs in marine aquariums.

Plant Bulbs

These bulbs are used to stimulate the growth of aquarium plants. They produce light in both the red and blue ends of the visible spectrum, which will allow plants to thrive. These bulbs are best suited to heavily planted aquariums.

Daylight or Full Spectrum Bulbs

These lights emit all colors of the visible spectrum and most closely approximate natural sunlight. Since they blend all the colors light, they are a good, general purpose light bulb. They are suitable for all types of fresh or saltwater aquariums.

Choosing the Correct Wattage Aquarium Bulbs

In addition to choosing the right type of bulb, it is also important to choose a bulb with the appropriate wattage. Choosing either undersized or oversized bulbs can have a detrimental effect on aquarium residents and limit or distort the view to people viewing the tank. The following is good general guideline to follow when choosing bulbs:

  • For fish only aquariums, use 1 to 2 watts per gallon.
  • For freshwater aquariums with live plants, use 2 to 5 watts per gallon.
  • For saltwater or reef aquariums, us 4 to 8 watts per gallon.

Choosing Lighting Style

Aquarium Light Bulbs

Aquarium light fixtures can be grouped into three main categories, each with its own advantages. This selection allows the hobbyist to further customize the lighting system to meet the needs of the individual aquarium.

Normal Fluorescent Bulbs

Also known as standard fluorescent bulbs, these are a good choice for either fresh or saltwater aquariums. They are affordable, easy to use and economical. There is a wide selection of these bulbs which allows for a great deal of customization to meet the aquarium's specific needs.

Compact Fluorescent Bulbs

Compact fluorescents are a higher output type of bulb. This allows one compact bulb to do the same duty as two standard fluorescents. They are also easy to use, available in a wide selection and have the added benefit of compactness, which can also help to save space. They are also a good choice for either fresh or saltwater aquariums.

Metal Halide Bulbs

These are high intensity bulbs that are popular among advanced aquarium hobbyists. They are best suited for aquariums with high lighting demands, such as a reef aquarium, or for large sixed tanks where standard lighting will not penetrate fully.

There are many options when it comes to aquarium lighting systems. By choosing the right color, style and intensity of aquarium light bulbs, the hobbyist can provide a healthy environment for the plants and animals inside and an enjoyable vista for the viewer on the outside.