beginning of algae?

[TankBoss]

I had a noticeable white fuzz on all walls of my tank today. I thought my new t5 ho lights were to blame for washing-out the colors of my fish and rock... turns out the light white fuzz was the issue. After after scrubbing it off I was able to appreciate the actinic and white bulbs I put in.
I'm just curious as to what the fuzz was... was it algae? So tiny that I was only able to see it with my eyeballs practically touching the tank. When I was up close I could see its movement in the water.