Maybe better algae growth is just the result of a bulb putting out more light? Over time the lights get dimmer. For just seeing the fish, it's not as big of a deal, but for plants you would periodically replace older bulbs with new ones.
I was looking for more algae growth in my mbuna tank, so I tossed a spare 48" bulb in the fixture. It didn't look as bright as the other one, so I took a stroll through the lighting section at HD. I picked up a "plant and aquarium" bulb for the mbuna tank. I'm hoping the algae growth increases. It gave the tank a little bit more purplish look, but I think it's alright.
I also saw "Daylight Deluxe" bulbs, which had a 6500k rating, so I picked a couple of those up as well, but I haven't had a chance to try them out yet. I did find the spectrum online and it looked decent, so we'll see shortly if it helps bring out blues a bit more.