Color Temperature and it's Effect on Coral

[njhcnwk]

There seems to be a whole world of actinic bulb colors as well as daylight bulbs. I was wondering what the difference between 10,000 and 20,000K would be. Also I'm wondering if someone can break down actinic colors for me. I see all kinds of shades of blue and purple and pink and i'd really like to know what they accomplish.

[Zebodog]

Here's a good read on actinic lighting. http://www.reefs.org/library/article/actinic_lighting.html
You'll find many other good articles and discussions with a quick google search.

As for the difference between 10,000k and 20,000k it is normally a measure of the colour temperature of the bulbs where the higher number, in this case 20,000 measured in Kelvin (K) represents a bluer spectrum. Daylight on an overcast day is considered to be somewhere near the 6,500k. The higher rated bulbs tend to simulate deep water more effectively as they tend to produce higher light output around the 420nm to 460nm wavelength (similar to actinic.)

You'll find this to be very subjective however as there is really little standardization amongst manufacturers and any one given bulb could look completely different depending on the ballast used to fire it.

[BR12349]

what a great article