I have been dealing with an algae issue for a few months now. Totally my fault (I guess it always is!) but I didn't change my ro filters and my tds crept up. Changed everything in the unit out, including the membrane probably 2 months ago. The hair algae was pretty established and despite numerous scrubbings with a toothbrush, I couldn't get it off. Well, today I decided to pull out the big guns and pull out all my rock and hit it with peroxide. I had hesitated to do this, as I really liked my rockscape, but finally was sick of the algae. Took about 2.5 hours, for 4 rocks and 2 branches to be pulled and cleaned and put back together. Also broke a few colonies and pulled my tricolor out all together. I am keeping my fingers crossed that I don't have any casualties, but my female flame wrasse was in my holding bucket after hitching a ride in the rock, and when I got her back in the tank, she looked pretty shaken up. I have also been dealing with low mag numbers, and bringing it back up has taken a lot of product! But, it's trending in the right direction finally. Here are the nasty before pics, my hands were too gross to get any real during shots, but the algae foams up nicely and creates a nice green foam!