I know what algae you're talking about, be darned if I can find it on the net though. I had it constantly growing on the back glass and it grew longer in areas that the powerhead hit. I just constantly went in and brushed it off the glass before I'd do a water change. I would get as much of it off as I could. Eventually it would grow back in patches but less than before. Eventually I heated my tank up to about 90F and now I only have a very small patch on some rock. I don't recommend this method. I do agree that this algae really does a number on coralline algae. My coralline is just starting to come back on the glass.
Try looking at photos of Lyngbia or Hincksia. I don't think either is "quite" right but one may look close to yours. Unfortunately neither is very palatable to herbivores.
