Lighting an aquarium require understanding the effect of light on organisms in the tank, as well as understanding the technology that can be used to provide that light. While many people may choose to use a light fixture that they already owns or have in there home, the lighting that may be appropriate for a community tank with only fish may not be appropriate for tanks that contain plants or corals. Each type of lighting technology provide light in a different way than others, so understanding the contents of the tank will allow a person to make an appropriate selection of lighting technology.
LED lighting fixtures provides a variety of benefits over other types of lighting; they allow for the control of the spectrum of light that is provided to the tank, they run cool when they are in operation, and they use less electricity than other types of lighting. Fluorescent tubes provides solid lighting output to the aquariums at a relatively low cost, but the lights have to be replaced more frequently than LED lights. Metal halide lamps emit a very intense light that can travel deep into tall tanks, but they also generate a significant amount of heat that increase the electricity costs for the aquarium.
How to Light Your Aquarium
Besides determining the type of light that should be provided to the tank, the spectrum of that light is just as important to consider. Light travels through the water in specific wavelengths. For aquarium plants, it is important for the light to contain wavelengths that will trigger the appropriate biological response in those plants.
For example, blue light wavelengths drives the process of photosynthesis within the plants in both marine and freshwater ecosystems, while the presence of red light wavelengths will help the plants to produce the chlorophyll that they require to perform those photosynthetic processes. Full-spectrum bulbs emit light that appears to be daylight to the human eye and are around 6500K in color temperature. Use of the color bands indicated in the infographic will help to ensure that the aquarium receives the correct colors of light, which will ensure that the owner does not have to guess as to the light spectrum that is required by their individual tank.
In addition to the spectrum of the light that is provided to the aquarium, it is also critical to consider the duration of time that the lights are to be running. The duration that the lights should be on will depend upon the type of aquarium that is to be created. For example, fish-only tanks typically require shorter periods of lighting to avoid the growth of algae.
Low-light (or shade-tolerant) plants like Java fern and Anubias require light periods of eight to ten hours per day. High-tech planted tanks that use CO2 injection to facilitate the growth of their plants require exposure to light for ten to twelve hours per day. These different time periods is created based off the energy requirements of the plants in those tanks, as well as the need to avoid the rapid growth of algae in those tanks.
Because the requirements of different types of plants differs from other plants within the aquarium, the amount of light that each plant species receives should also be different from the other plants in that tank. Some plant species may require very little light to perform there photosynthetic processes, while other species may require intense lighting to facilitate their growth as thick carpets at the bottom of the aquarium, or to maintain there compactness. The use of PAR ranges ensures that the light intensity that is provided to the aquarium is appropriate for each of the species of plants that live within that aquarium.
For instance, Java fern plants can grow in the shade created beneath another plant that floats on the surface of the tank, but other species like dwarf baby tears will stretch out thin if there isnt enough light provided to the bottom of the tank. Beyond the spectrum and the intensity of the light that is provided to the aquarium, the placement of the lights within the tank and the timing that they are turned on and off will also affect the results of lighting the tank. Lights that are placed close to the surface of the tank will emit the maximum amount of light into the tank, which is a benefit for tanks that are deep into the aquarium.
Suspended lights, in contrast, will disperse the light over a greater portion of the tank, which is beneficial for aquariums whose design allows for the tanks to remain open and clear of covers. The use of a timer to control when the lights are on and off will provide benefits to the fish that live in the tank; the consistent schedule will reduce the stress that the fish may experience, as well as avoid the rapid growth of algae within the tank. The majority of problems that develop in the aquarium can be attributed to one general problem: incorrect light levels or incorrect light schedules for that tank.
Providing too much light to the tank, or providing light to the aquarium for too long with the lighting schedule, will result in the growth of green water and hair algae. Providing too little light will lead to the plants within the aquarium becoming pale and leggy. Sudden changes in the intensity of light in the tank or sudden changes to the light schedule will also stress the fish that live within the tank; fish are genetically programmed to expect changes in the light level in the water when it is sunrise or sunset each day.
Identification of these issues on the troubleshooting schedule will allow for the owner to address these problems appropriately. Following these suggestions will help to maintain a stable tank and the fish that live within it. For example, it is necessary to measure the light intensity within the aquarium at the substrate level, instead of using the specifications of the light manufacturer.
If there is algae present within the tank, it may be beneficial to add a “siesta” to the tanks light schedule. The use of reflectors to tank hoods will allow the aquarium to better capture the light that is produced by the tank, as the reflectors will prevent the light from bouncing off of the ceiling of the aquarium. Finally, ramping up the light intensity gradually will allow for the same benefit as ramping the intensity down; it will prevent the stress that can be placed upon the fish if the lights are turned on at full intensity.
Thus, lighting an aquarium can be used to provide the livestock in that tank with the correct amount and type of wavelengths for the correct duration of time, which will help to maintain the balance of the entire aquarium system.
