I run a UV sterilizer on my 180g. I have run one since the beginning when I had an ick outbreak. A few fish survived, and I don't know if that helped, but hey I just had it sitting there so why not use it. And I don't like to use emerald crabs for bubble algae. They bust them which makes it spread. You are better off removing the rock and try to remove the bubble intact. OR use a hose to try and suction them off the rock, that way if you bust one, you are less likely to spread the spores. It can become like a plaque if your not careful. Some like it in their tanks, and some dont. I don't.