+1 Looks like bryopsis (can't tell for sure from the picture though)
+1 Kent Marine Tech M (This stuff wiped it out perfectly with no side effects other than maybe a small snail or two)
I had this and nothing would get rid of it. I read all there is on the internet and the Kent Marine seemed worth trying. There are a couple of people with exact instrcutions. I followed them and it all just dissolved in about 1 week to a week and a half. Kept up the Mag level for another couple of weeks to be sure and it has not been back in 4 months. It worked like a charm. (I didn't have to pull it or anything, it just dissolved). Use the Kent (not just any Magnesium).
+1 Kent Marine Tech M (This stuff wiped it out perfectly with no side effects other than maybe a small snail or two)
I had this and nothing would get rid of it. I read all there is on the internet and the Kent Marine seemed worth trying. There are a couple of people with exact instrcutions. I followed them and it all just dissolved in about 1 week to a week and a half. Kept up the Mag level for another couple of weeks to be sure and it has not been back in 4 months. It worked like a charm. (I didn't have to pull it or anything, it just dissolved). Use the Kent (not just any Magnesium).