What Is a T12 Fluorescent Tube?

A T12 fluorescent tube is one of many commercially available forms of fluorescent lighting. Once the industry standard, they are slowly being replaced with better quality, lower energy-consumption forms of lighting both in homes and over aquariums.

  1. Why T12?

    • T12 bulbs, like most straight-pin style tube lights, are named by the bulb's diameter in twelfths of inches. Thus, a T12 bulb is 12/12ths inches, or one inch in diameter.

    Aquarium Use

    • T12s are have been the standard bulb types in most pet store aquarium packages, and many single-lamp aquarium hoods still use T12 for basic lighting today.

    Replacements

    • In the past decade, T8 and T5 lighting have hit the market. Both bulb types are capable of producing the same light output as the old T12 bulbs, but in smaller sized tubes. This means that more watts of light can be fit into the same space in your aquarium hood.

    Energy Savings

    • Newer T8 and T5 bulbs are also considered "energy saver" bulbs, which draw on somewhat less power to operate at the same lumen output as the T12. Depending on how many ballasts you operate, this could mean considerable energy savings over time.

    Planted Tanks

    • T12 lights have always been inefficient over the planted aquarium, which requires a much higher wattage than a simple viewing light. The increase in popularity of T8 and T5 lighting in these aquariums will likely mean the eventual end of T12s for aquarium use.