Actinic light promotes the growth of Zoaxanthellae algae, essential for the growth and well-being of all photosynthetic corals and invertebrates (not macro algae). However, Actinic and strong blue spectrum lighting is visibly blue and will definitely need a full spectrum bulb to help offset the color distortion.
The color temperature of light is the ratio of red to blue light waves measured in degrees Kelvin (K). At 6000 degrees (K), the ratio between red and blue is equal. The lower the content of blue light waves, the lower the color temperature. During the day, the color temperature of sunlight varies. It also changes at different depths underwater as reds are filtered out more rapidly than blues.
Although blue spectrums penetrate deeper into water, species which live fairly deep rarely see the red end of the spectrum because it is filtered out by the water. They can actually be "bleached" to colorless by a light that is too intense. A "K" or Kelvin rating of 5000-5500 is a good estimate to simulate a noon sun in most tropical environments.
That was taken off a site I had bookmarked about lighting.
I have a 24 gal aquapod, that came with a 32 watt 6700/10000k duel compact and a 32 watt 50/50 actnic, I took out the actinic and put in another 32 watt 6700/10000k.
Needless to say I have more then tnough for all my plants I have in it, with some eco-complete and a dyi co2.
And the betta I have in there looks great, nice smoth even natural colors. like he does if i have him out in a container when I clean the tank
