You haven't said if you are using the Killer or Professional version of your board.
In the manual for the Killer, it states that there are 2 LED indicators, Bios A Led and Bios B Led. The lit up LED indicates which BIOS you are using. The colour isn't mentioned.
If your computer is booting up, etc, just great, then the BIOS is working, the Red LED will just be an indicator and the colour shouldn't make a difference.
I noticed in several reviews they rave about the red colour scheme and red accents for the Z87 Fatal1ty Professional MB. Maybe the red LED is in keeping with that??!!