I recently installed 2 sea swirls on my tank and a ReefresH20 9"x9"x4" block in my sump next to my skimmer. I am getting more bubbles in my tank than I have ever gotten before the sea swirl install. I am now fighting a bryopsis algae and now a brown I think type of cyano algae. it's not red slime algae its brown. My Fowlers and bariene tang eat it but it's growing and covering my rocks like crazy. I have had the tank running for over 3 years now, but recently changed the rock work around and removed 4 inches of sand about a month ago. now I have a bare bottom tank except in a few places where it is about a half inch deep where my engineer gobies and diamond goby eat and hang around. I don't know what could be causing the bubbles and don't know if the bubbles are creating the brown slime algae. I only dealt with the brown slime when I first set up my tank 3 years ago and used red slime algae remover and it went away. anybody use sea swirls and have a bubble problem or is the ReefresH20 block causing or adding to the bubble problem? Please help. At a lost of words. I even turey baste the rocks clean from the slime algae and it comes right back the next day. Nitrates are at 15ppm and have dropped from 20 ppm but the Nitrates have been at 20 for well over 4 months now and did not have the slime algae.