I have been battling this for the last couple months. It is a brown algae/dinos that covers the back wall of the tank, rocks and sand. It is much worse during the day and blows off easily with a turkey baster. I have some pictures I took through a microscope, hopefully they are clear enough for a good ID. Would like a positive ID from those of you that are knowledgeable in this area so I know how to proceed. Thank You for any help!!