Thanks for the replies. Do you have a name for this stuff? I have it growing in a couple of locations now and I think I'll let it grow a little more before I get one yellow tang. I have
a 75-gallon so I think I could keep one tang as I only have one Royal Gramma at this point.
It is a red macro algae. Over the years I have had two variations appear. The only time I have gotten it was when my 5500/6500 bulbs reached 14 months or longer. This is due to a spectrum shift. I would bet that the rock that it is growing from is carribean in origin. When you change your bulbs, it will die off.