I just got home for Winter break and my tank had a few things that I really didnt care for. It had brown algae on the return box and if you looked at the tank from the long side (6ft) it had a slight yellowish tent to it. It wasnt a bad tent at all, but I would prefer for it not to be there at all. I have a UV sterilizer and a protein skimmer, so I don't really know how it could of started. Does anyone know how to prevent this and control this. My tank has been cycled for about 7 months. Thanks for everything.