Been using this now for around 3 months or so after seeing it at a guys house with a sick SPS tank and figured if try it. At first I started at 1/2 dose for 2 weeks and went up 5 ml every 2 weeks dosing twice a week. Had small brown algae film on glass and cutting board but went away after a few weeks. With that being said my polyps are stretched to capacity, color has been incredible and I'm getting more growth them I ever have in any setup I've ever had. Now I've tried a lot of products in my 8 years in the hobby and most did nothing but drain my wallet but for 20 dollars for a 1 liter bottle it's worth every penny 



