Agree that when adding clowns to a tank, having one a little bigger then the other makes it easier on the fish due to a little less bickering as they grow and as one gains dominance over the other.
There have been some successes with a large harem of clownfish being added to a large tank (usually an anemone is involved) where they do fine. But, in smaller tanks it is best to either have only one or two, but not more. If it is a long enough tank some have had two pairs, but again success rates are low. That doesn't mean you won't hear someone say they did it w/o issue. What it means is that they are the exception not the norm. And you need to take into account how long they've had that success. 1 year or so if not so successful compared to those of us who have had paired clowns for greater than 5 years.
My two B&W clowns just turned 6 years old in October (captive breed, bought locally from reefer). Here they are in March 2012 at five months old.
And in 2016 laying eggs
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