I just received my Algae Mower Vac and started using it on my hair algae and bubble algae. I have also used it on some brown algae on the surface of the rocks, it just mows that right off. The tool works very well and as long as you take your time it will easily eradicate the algae. I haven't used the sand cleaning feature yet, but I will in the next few days. I am very happy with my Algae Mower Vac. It will greatly enhance the look of my aquarium.