Should you buy fish in pairs?

Question
another angel fish question . I have a large angel fish in a 55gal tank should i get another angel fish as I have heard you should always have at least a pair?  thx

Answer
Hi Jasmine:  I try to buy fish in pair I think on some level it adds to their life to have similar company.  If you add another angelfish to your tank... I would make sure it is as large as the one you have and in fact I would add two... not just one just in case there is some aggression.  dave