You can buy the different bulbs for the fixtures.
I swapped out my "actinics" that were included with my fixture for 03 True Actinics from a third-party provider. They look very different when they are on (purple rather than blue), and they emphasize the 420 range of lighting (which is what zoaxanthallae (sp?) like.
The standard actinics are indded just painted blue. This does two bad things: (i) it does not highlight the 420 range, rather it just blocks out light in the other ranges, and (ii) by blocking out other light, it really reduces the lights output....turnign a 65 watt bulb into something far less efficient.
The true actinic 03 bulbs are well worth the money for good bulbs in my opinon. My corals have really liked the change.
HTH
Stewart