Ultraviolet (UV) light is electromagnetic radiation with a wavelength shorter than that of visible light, but longer than soft X-rays. It is so named because the spectrum starts with wavelengths slightly shorter than the wavelength humans identify as the color violet (purple).
Using UV wavelength radiation to destroy contaminants in water. UV light is also used to create ozone molecules for the same purpose.
The lower collection system in a filter which directs filtered water back towards the pool. It also distributes water in reverse during backwashing. Also see laterals.
Also see: LATERALS