adding anthias

[atlMreef]

i currently have a 240 gallon reef tank and i have a trio of bartlets anthias and i wanted to know if and how it would be possible to add a few more my current live stock is 1 purple tang 1 regal tang 1 blonde naso tang 1 red sea sailfin tang 1 male and female mccullochi dotty back and a bonded pair of sleeper yellow headed gobies (or something like that)