LED Lighting for Your Freshwater Aquarium

Pros and Cons

aquarium with LED lighting
Kaknogler/Pixabay

When it comes to aquarium lights, light-emitting diode (LED) lighting is the new kid on the block. Although the reef world dove into LEDs in a big way, the freshwater world was a bit slower to embrace its use. But as the field rapidly expanded, more and more options have become available. There are some excellent applications for LED lights in freshwater aquariums.

The Pros

The benefits of using LED lights are many. They take less energy to run—quite a bit less. LED aquarium lighting uses up to 80 percent less electricity than other aquarium lights. They also do not generate the heat that fluorescent light bulbs do, and so they won't heat up your aquarium water. However, they still need good air circulation so the heat they put off doesn't degrade the lifespan of the LED chip, and keep them away from other types of lighting.

A very popular advantage of LED lights is the fact that they last far longer than other traditional types of lighting. LED lights last for up to 50,000 hours (almost six years) as compared with two to four months for incandescent bulbs, six to 18 months for standard fluorescent bulbs and metal halide bulbs, and up to 28 months for compact fluorescent bulbs.

LED lights can be dimmed and programmed, allowing for a natural dimming at sunset and the reverse at sunrise. This is particularly good for nocturnal fish, as a dim blue light can be left on the tank to simulate moonlight and allow for feeding and viewing purposes. There are even LED lighting strips that replicate the monthly lunar cycle. You can have fun changing the light with the remote or app. Or, let your smart lighting system determine itself the temperature and the stage of plant growth and select the right colors and wavelengths.

LED lights come in a variety of colors, which can be used to accent the tank in interesting ways. They are marketed by spectrum (often in the Kelvin or K system) and you can choose which suits your purpose. For example, 8,000K white spectrum promotes photosynthesis of your plants and enhances the colors of orange, red, and yellow fish. Add a magenta or magenta/blue LED and you also bring out greens, blues, and reds while proving more support for your plants. The 12K white and magenta combination can be perfect for planted aquariums. If you want a night lunar light that will make your fluorescent fish glow, 445-nanometer royal blue lights are popular. There are even arrays with different colors of LED lights you can program for your needs.

Because LED lights are usually arrayed in a strip, you can get coverage over a wide area of your tank.

The summary of the pros include:

  • Low energy consumption
  • Low heat output
  • Long life
  • Color options
  • Adjustable light intensity
  • Nocturnal lighting

The Cons

At the onset of LED lights, there were a number of negatives, but over time the technology has improved to the point that there are very few cons for this type of light.

Many aquarium kits that include a light or hood with a light do not offer LED lights. Popular combination units, such as the Eclipse systems, are only offered with standard fluorescent light bulbs. However, you can find LED options to retrofit your Eclipse hoods.

Likewise, most light fixtures are still offered primarily with fluorescent lights. The LED fixtures that exist tend to be a bit more costly to purchase upfront, but you'll more than make up for it over time in energy savings as well as bulb replacement costs.

The other primary weakness is in the area of planted aquariums. Many LED light fixtures are only suited for low to medium lighting needs. That will do nicely for virtually all fish and for a number of plants. Kelvin ratings of 6500K to 7000K are best for most planted aquariums. For plants that have high light needs, however, you will have to search for good LED lighting options.

Summary of the cons for LED aquarium lighting:

  • May not be as available as other lighting options
  • Initial cost is higher
  • May not be suitable for high lighting needs

The LED field is rapidly expanding with new products. Most experts agree the future is bright for LEDs.