I found that the product does work. However, it seems to create a very light purple colored coraline that just does not look natural to me. Also, EVERYTHING (including tank walls and overflows and powerheads) being covered in coraline also looks bad to me. I like a nice clean natural look. And to achieve this look, I found that simply maintaining 450-500 ppm calcium worked the best for me. I also introduced a nice piece of liverock that I purchased cured from my lfs for $50 that was covered in a nice deep purple coraline growth. I placed this in front of a powerhead, as that is supposed to help the coraline spread. Good luck!