you should get the orp controller. I have the enaly unit which robthorn was trying to describe. Its great. I get clear water, I can keep more fish and I can over feed and not worry. My lps have thicker polyps too. I keep it around 380 mv to be safe. Make sure your skimmer can process the ozone correctly or you will smell it in your house. The side effects to humans have been blown out of proportion. I have a copier in my office that leaks more ozone than my enaly unit. You should also get an air dryer