Lighting is a very important part of any custom aquarium system. However, each type of aquarium setup has specific lighting requirements. There are 3 common groups of setups to be considered: fish only (freshwater or marine), live-plants (freshwater only), and reef (marine only).
Regardless of the type of setup you have, it is important aquarium maintenance to replace ALL of your light bulbs every 9-12 months. As a bulb is used over long periods of time, its output spectrum deteriorates. After approximately 9-12 months, the remaining spectrum will promote unwanted and excessive algae growth. Another important lighting fact is the need to have them on an appropriate time cycle. Every aquarium needs to have a “day” and a “night” cycle. Fish do not have eyelids so, in order to rest, they require a period of darkness in the aquarium. This cycle can be manipulated to suit your schedule but it needs to be relatively consistent.
Plants and some corals use light for energy but, make no mistake, corals are NOT plants. Corals are invertebrate animals, some of which have algae living in their outer tissue. This is called a commensal relationship. The coral protects the algae by allowing it to live inside its skin and the algae uses light to produce sugars through photosynthesis. The coral then uses those sugars for energy. Plants and alga perform different functions in light then they do in darkness and these functions are important to their health, therefore it is important to provide plants and corals with an appropriate light cycle.
Most reef and live-plant hobbyists know the inhabitants of their aquariums require light as a source of energy. Most of these hobbyists are also aware that they are recommended to use 2-4 watts per gallon for a live-plant setup and 3-5 watts per gallon for a reef setup. What some of these hobbyists do NOT know is what type of lighting to use or what spectrum will be most beneficial for their specific setup.
In a reef aquarium, a high-intensity bulb, such as a metal halide bulb, will give the best coral growth rates and deepest light penetration to the lower parts of the aquarium (water filters out light intensity very quickly). The downside to these high-intensity bulbs is cost. They are expensive to purchase and draw a tremendous amount of electricity so they are expensive to operate as well. They will also generate excessive amounts of heat and may necessitate the use of a chiller to keep the aquarium at the right temperature. Chillers are also expensive to purchase and operate.
Some alternatives to metal-halide bulbs include a range of florescent bulbs:
- Very-High-Output (VHO)
- Power-Compact (PC)
Yet another alternative is the use of LED bulbs although these are expensive to purchase. Most hobbyists choose the fluorescent bulbs since they are the least expensive to purchase and operate yet still yield acceptable results.
For more information on aquarium lighting, contact Diamond Aquatics and we will be happy to answer any questions you have.