Thinking of getting some berghia......

[Timbits]

Getting fed up with the aptasia, I think I need to get some berghia.
I know that peppermint shrimp will eat the berghia but how about cleaner shrimp? I have one in my tank. My tank is a 40 breeder. Live stock is 2 clowns, starry blenny, tail spot blenny, bangaii cardinal, mandarin dragonet, and cleaner shrimp. I'm worried about the cleaner shrimp and mandarin dragonet might eat the berghia? Any thoughts? Also how many berghia should I get? I wouldn't say the tank is completely overrun by aptasia but there's a fair bit. Thanks.