LEDs - Well, this is interesting

[mike31154]

Originally Posted by Ron99

Kessil's have UV but barely. Around 390nm or 385nm IIRC. So in my opinion it's more a marketing thing than a real "UV" advantage. What might make the Kessil work well is the amount of light being put out around that range rather than the actual; wavelength. i think the Kessil has more violet than some other fixtures. One outputting the same amount of light at 405 or 410 might well perform just as well.

UV comes in different flavours(wavelengths), A,B,C. You probably don't want to be exposed to UVB or UVC for any length of time due to the potential health risks. Manufacturers of light fixtures available to the general public are no doubt keenly aware of that. Legislated marketing... The point is, Kessil does provide some UV which is generally acknowledged to aid certain coral growth.