nah they're ok as long as everyone else in the tank is bigger than them.... i've got a gold tail that i've had since i started my first tank in july of 02', he thinks he's tough but all the other fish know better. the funniest thing is that he is still exactly the same size he was when i bought him almost 3 years ago
another thing you could try is rearranging your rockwork so that he has to re-establish his territory with the other fish in there, that is, if you want to keep him
