Just got back from vacation. I was gone for four days. My daughter feed my fish for me. I think she feed them a bit much, but they ate. I just got done with the water changes and noticed on two of the tanks that there is what looks like air bubbles on the glass. At a closer look they are some sort of algea. Tried to get a pic of it put you can't really see. I was just wondering if someone knew what it was. I was thinking that there may have been too much lights on while I was gone.