[Bogie]

Well, I couldn't get the water parameters posted eariler.
I was fertilizing the lawn this weekend, and I didn't want to take a chance with any of the nitrates from the fertilizer getting from my shoes to hands to tank... it's toxic for the fish. So no hands in the tank for a few days.
This morning I did 3 tests, I'll add the other parameters later, when I have more time in the afternoon.
I didn't do pH, b/c I don't do pH testing in the morning before the lights come on.

Ammonia = 0 ppm
Nitrate = 0 ppm
Nitrite = 0 ppm

So if everything else is withing good range, have more than enough flow, and the daylight lights are only on 8 hours, what could be causing this algea all over the sand?