mhucasey
Acros & wieners, oh my!
Lamps in the 6500 k usually have more par and a wider spectrum of light..
Actually some 6500k lamps have almost more blue than bluer lamps.. The bluer lamps usually just have less of the other spectrum's..
Yes par is not a issue much anymore if you have a decent fixture and lamps.. This is halides, T5 and leds so basically it comes down to spectrum and what you like.
What I don't think people realize is coloration has to do almost as much with spectrum the coral prefers as well as spectrum a coral does not like.. Corals don't care for red or uv so they create pigments and proteins to either block or change the colors of these spectrum's of light .. These proteins and pigments are what create the colors in corals.. There are also ones that are made to enhance the spectrum they like..
This is mainly with sps and shallower water corals that are used to a wide spectrum of light and UV.
People focus so much on par because of photosynthesis but there is so much more ..
One last thing, you are right on when you say par is not an issue with these fixtures. My shallow reef has two 6 bulb fixtures and corals have done better with it high up rather than lower. One LFS near me is not bringing in a selection of Aussie SPS anymore because he said they are being collected at deeper points and they don't do well with the amount of light we cook our reefs with.
T5s were trying to emulate the punch of MH, but if you look at a lot of Par maps for MH tanks, the T5 Par exceeds that easily. Not a lot of MH tanks can boast over 300 par near the sand.