New tank, had a major diatom and small cell amphidinium bloom. At one point dosed silicates to combat amphi dinos but that failed. Since it was small cell, I installed UV 2 days ago, and tank seems free of small amphi dinos. This other stuff has been growing on my rocks and back wall. It looks like soft hair algae and is very easily brushed off with a tooth brush. Photo and microscope pic below. Seems there are 2 types of algae
400x magnification
400x magnification