So I've had my tank set up for over a year. Couple weeks ago I had brown stringy algae come in I was using vibrant. And got on here and someone was talking about a black out and peroxide so I started the process did it for 3 days after the 3 days it was basically gone little pieces here and there. In the process i think i lost my pineapple tree coral but everything else is fine Couple days later I see it on the sand a very light layer so I suck it out and Couple days later back again I lowered my light a little more and the layer got even thinner and just today I had a little on my corals and they weren't coming out so my question is how do I keep it away?

