So here's something interesting I noticed last night.
With my power heads all cleaned off, I can now better see how quickly this stuff grows. I got home yeseterday and they were already starting to get covered in a light dull green dusty mass. I started unplugging and replugging in the powerheads and when I did this the force would suck some of this algae in to the powerhead and it would get blown out into the water. If I had to describe its appearance I would say it was like watching somebody blow the dust bunnies off a feather duster. Yeah, pretty much EXACTLY like that. So now after just one full day after having cleaned off everything, if I did this on/off thing with one or two of my powerheads, my tank now had algae dust bunnies all over the place!
So now I'm wondering if all these powerheads are doing more harm than good. All i can see is algae growing on them and then being spread through my water. So i removed all but the Tunze, which is still giving my tank 24x it's volume in flow, not including the main water pump. Before I had 5 powerheads, all collecting thick algae as well as the two water return lines. Now I'm down to just one powerhead and I raised the water return lines so they are just above the surface of the water. So only one "algae magnet" remains in the tank.