Yes apologies, Microbacter Clean. I followed the instructions and it took several weeks before I saw much difference. I had been battling hair algae for years and I mean years. The reason is I brought some old rock taken from another aquarium and it was continually leaching phosphate. I tried Rowaphos but the algae was still there. I pretty much gave in and just got into a routine of removing as much as I could with every water change when I heard the owner of Brightwell being interviewed on one of the reef podcasts. He was talking about this product and another one called Razor. I am not one to fall for a sales pitch but thought hell, I will give it a go (Microbacter Clean, not Razer).
I now dose a small amount with each water change and and very happy with the results.
I am not saying it is a miracle cure for all algae and for every tank as one thing I think we have all learnt over the years is that no two tanks run the same. However for me, this is one of a very few products that I have used that I would recommend for people with hair algae growing on their rocks.
Hope this is useful.