Aquatic plants, like terrestrial plants, need sunlight to make food, through a process known as photosynthesis. The best aquarium lights for plants provide full-spectrum light without excess heat that can harm fish. Among the many light choices on the market, fluorescent tubes, power compact fluorescent bulbs and metal halide lighting are suitable for freshwater aquariums with plants.
For an aquarium hobbyist on a tight budget, fluorescent lights are the best choice. Tube fluorescent bulbs provide adequate lighting for smaller aquariums. High-output (HO) and very-high-output (VHO) lights penetrate the water in deeper tanks to reach plants near the bottom. They provide the complete light spectrum that aquarium plants need to thrive without raising water temperature.
Power Compact Fluorescents
Power compact fluorescent bulbs are the latest addition to aquarium lighting. Some hobbyists consider them superior to normal-output, HO and VHO fluorescent tubes because they use less energy to create the same light. Power compacts take up less space and provide a modern, streamlined look, making these the best choice for hobbyists seeking a sleek look for their aquarium setup.
Metal halide bulbs provide full spectrum light for plants. They're prized for their ability to mimic the effects of natural light underwater. Light emits from a single point along the fixture; a large aquarium may need several bulbs. Because they require ballasts and special fixtures, they are the most expensive among lighting options for aquarium plants. For those seeking aesthetically pleasing fixtures that provide full-spectrum light, metal halide bulbs are the best on the market.
Set your lights on a timer or manually turn the lights off at night. You'll save energy and money while mimicking natural day and night cycles. Fish and plants stay healthier when their aquarium environment matches their natural habitat. Use only fixtures marked for aquarium use. Never handle hot bulbs. Always unplug the fixture before moving it or replacing bulbs, to avoid electrical shocks.
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