The tank is a year old and I had a light go out on one side a few weeks ago,well turned out it was the ballast and not the bulb but I broke one of the bulbs getting them out so I replaced both bulbs with new ones. I got a diatom like I expected but then it changed,At first I thought it was hair algae because it looks like hair but it is brown and ugly,comes off the rock and glass with minor rubbing with a tooth brush.But then comes right back.I have not seen diatom do this before so I am not sure that is what it is.It is on my sand in clogs and you can pick it up.It is driving me nuts..I cleaned everything yesterday and it looks sooooo pretty but I don't wont this back so any ideas..