I just read a post regarding Ich. One of the suggestions was to get a cleaner shrimp. I know from reading about them that they "clean" the fish of parasites and dead scales. Does this mean that it reduces the chance of the fish getting parasitic disease? In my 46 gallon I have a cleaner shrimp and my flame angel spends a good amount of time getting "groomed". None of the other fish, 3 green chromis and a blennie seem to allow any cleaning. I find this relationship facinating. I have a 75 gallon and would like to add cleaner shrimp to it. Can you keep more than one? If so how many would you suggest for a 75 gallon that will be a mini-reef .