![Picture](/uploads/4/8/1/0/4810798/published/20180227-140504.jpg?250)
It is round the side to the rear of my live rock in an area of relatively low flow and light and quite low down. It looks like small leaves or plates. I think it looks quite attractive and is different to anything else in my little reef set up. I don't think it is harmful or indicative of any underlying problems like the hair algae could be.
I have read about plating coralline algae and wonder if this might be a sample. I have good coralline growth on my rocks and glass so conditions could be right but I have never seen any of the plating type.
It may also be a type of red macro or micro algae. Will just have to wait and see what happens over time.