Why Do Saltwater Aquariums Prefer T5 Over T8?

Aquarium hobbyists must give careful thought to the right type of lighting for their tanks. Lighting not only illuminates the landscape of the tank interior, it provides light for plant photosynthesis. Lights also give off heat, so the correct lighting ensures that your fish will have a healthy environment. Though saltwater aquarium lighting is a controversial issue, many hobbyists prefer T5 lights over T8 lights for their tanks.

  1. Saltwater Aquarium Lighting

    • Saltwater tanks require a sufficient amount of light to keep fish healthy. These fish come from tropical and subtropical regions where sunlight filters through the various layers of water throughout the day. Saltwater tanks also may contain a number of life forms that require light, so aquarium hobbyists should take an inventory of what they want in their tanks before determining the type of lighting required. Plants, coral and beneficial algae all require light to thrive. Fish-only tanks, commonly called FO tanks, are easiest to light because photosynthesis is not an issue. Lamps such as the T5 fluorescent bulb must give out an even, adequate light while using energy efficiently enough to make them cost-effective for home aquariums.

    Types of Aquarium Lighting

    • The ̶0;T̶1; name in the lighting industry stands for tubular. The number after the T indicates the diameter of the tube used. So, T5 light is a tubular fluorescent light that has a diameter of 5/8 inch. The T8 light, another common light used for both freshwater and saltwater tanks, is also tubular in shape but has a 1-inch diameter. Other types of aquarium lights are available to hobbyists, such as metal halide lamps, but these give off large amounts of heat and use greater amounts of energy.

    About T5 Lights

    • The advantages of T5 lights are their compact size and energy efficiency. These lights fit easily under tank covers without taking up additional space that may be necessary for power or filtering equipment. T5 lights also are available in a high-output (HO) type that allows for more light with the same compact size. T5 lights are often preferred by aquarists because they last up to three years, according to the Aquarium Lighting Guide website. This longevity makes them a cost-effective choice for home saltwater aquariums. T5 lights come in a number of lengths to fit any size of tank.

    About T8 Lights

    • T8 lights are larger, with their 1-inch diameter. They cost more than T5 lights, though hobbyists that have many aquatic plants may prefer the larger size, as it illuminates a greater area. However, T8 lights can overheat a tank and lead to the loss of fish if not carefully regulated with timers. They also use more energy than the standard T5 lights.