Join Date: Nov 2003
Location: new york, new york
Kelvin really doesn't mean anything for plants. The bulbs that you want to stay away from are the actinic ones, which are high in the green area of the spectrum.
You want a bulb that is high in the blue and red areas of the color spectrum. This is the area that is most beneficial for your plants. All that Kelvin measures is what color the light appears to the human eye. At 8700K, that sounds like a nice comfortable level. Below 6000K, things appear too green.
Power compacts in general are a great choice, if not the best for tanks under 4 feet in length. They offer a great color choice for you (Kelvin), Long life, little degradation, and they pretty much provide even lighting amounts.
With bulbs, PAR, or photosynthetic radiation, gives us the best idea as to how great the bulb is for our plants. Unfortunately, most bulbs do not provide this information.
I think your plants will be fine. How big's your tank?