Katchan,Durbkat, as a general rule if its to big to fit in an angels mouth its safe
. The only other time to worry (in a tank that size) is breeding time (if you end up with a pair) but a tank that size the other fish should be able stay out of the angels way
Andrew
I hope you don't mean to imply that just being alive is the same thing as being safe. It's not.
Stress is harmful to fish and having an aggressive tankmate is a major cause of it. Since they are living in a relatively small space, they cannot escape to freedom. Eventually, even if they are not killed outright, they are apt to slowly decline and eventually become sick and die.

EDIT: apogises to Durkbat for hijacking thread.