Here are two photo's of the same exact tank taken about a week apart, the only difference is the bulbs everything else is exactly the same. (sorry about the one being blurry, stupid phone camera, and excuse the plant mess, I was neglecting the scape while setting up my reef, she's all cleaned up now)
Anywho, one is a photo while running the Aqueon 8000k the other while running a Life-Glo 6700k. The 8000k emits more of a purple light (not nearly as bad as the "plant bulbs" do though but noticeable by looking at the reflection from the black background) Comparing the spectrum you can see why. The Aqueon is high in the Red/Blue spectrum but lower in the yellow/green while the Life-Glo peaks in the yellow/green. Makes sense.
I "tested" (after a few too many beers mind you) the lights with a white sheet of paper on the floor of a dark room. I in no way expected accurate scientific results, just wanted to see if there was a large difference between the two. To the (drunken) naked eye in a totally dark room the Aqueon emitted a less intense "dull purple" light onto the paper and was slightly below the Life-Glo in intensity (room was less bright). The Life-Glo bulb on the white paper was nearly pure white, not too much yellow and seemed to light up the room better. Could just be from the extra 3 watts though.
Most of the yellow/green you are seeing in your water is going to be either from the tannins/plants/decor reflecting more green/yellow light.
Now that's all good for "explaining" the visible color rendition of the bulbs to the naked eye. The ability for these two specific bulbs to support plant life was heavily discussed by Byron, Quantum, and myself in this thread http://www.tropicalfishkeeping.com/a...ok-like-89102/
The Aqueon in theory should be better for plants as it peaks in the red/blue... but... there are many many other variables other than spectrum alone that come into play.
I've personally used both bulbs and from my non-scientific observations in plant growth (comparing pictures over set amounts of time) the advantage very slightly goes to the Life-Glo (even though it's peak in the spectrum isn't as high in the blue/red areas). The vast change in appearance did take some getting used to though (wife likes the bright green better, mostly because it offsets/contrasts the enormous amount of blues/purples emitting from the reef tank 10ft away) I personally kind of liked the color of the Aqueon bulb, seemed as though it gave it a more natural color rather than the lime green from the Life-Glo. Either way though as I said the growth has been nearly comparable, with a very slight lean towards the Life-Glo which again could of been due to many other variables.
So since either one WILL support plant growth and rather comparably I'd say go with what you like the look of better.
Aqueon 8000k spectrum
Aqueon 8000k Photo
Hagen Life-Glo Spectrum
Hagen Life-Glo Photo
(sorry about the blurry photo, just to show color rendition)