High-intensity discharge (HID) light sources, such as metal halide and high-pressure sodium lamps, have long dominated the market for lighting indoor spaces with high ceilings. These "high-bay" spaces are typically found in warehouses, factories, large retail stores, and athletic facilities. In recent years, both HID and high-intensity fluorescent (HIF) technologies have improved, but HIF technology has retained a performance edge in most applications, and it continues to gain market share. The improvements in fluorescent lamps and the emergence of new HIF fixtures have made T8 fluorescent lighting the most cost-effective choice for lighting high indoor spaces. These HIF systems are more energy-efficient than HID solutions and feature lower lumen depreciation rates, better dimming options, virtually instant start-up and re-strike, better color rendition, and reduced glare.

Fluorescent lamps emit diffused light from long glass tubes. This characteristic of diffusivity has enabled fluorescent fixtures to dominate the market for lighting commercial, institutional, and industrial spaces with ceilings up to 5 meter height. In recent years, however, the emergence of more intense and efficient fluorescent lamps coupled with specially designed reflecting fixtures has enabled fluorescent systems to break through the ceiling-height barrier and compete directly with HID lamps in indoor applications. A High-efficient T8 highbay can be mounted at 11m height for shop floor lighting applications. Earlier rapid-start versions of T8 and T5 lamps were unable to turn on below 50°F, but now most fluorescents can start at temperatures as low as 0°F.

Aquarius T8 Fluorescent Highbays have seven advantages over similar HID fixtures: lower energy consumption, lower lumen depreciation rates, better dimming options, faster start-up and re-strike, better color rendition, more pupil lumens and reduced glare.