I got some Kenya trees on live rock a few months back and as time has passed this little green anenomie looking hitchhiker has grown,
I hope it's a good guy would really appreciate if anybody could I.D it
they are a pest and come in with frags and liverock pretty commonly. I would remove asap before it spreads. If you can remove the rock from the tank then you can scrape it off making sure to get it all or it will come back. Another option might be aiptasia X or lemon juice injected into the mouth and deep into the body if you cannot remove the rock from the tank. There is a question of the day on this very subject as far as what everyone has used to kill aiptasia and should work on manjo's I would think.
Edit here is the direct link to the question of the day I was speaking of.
Earlier this week we had a poll here where you voted on the best eradicator or aiptasia anemones! To my surprise the peppermint shrimp edged out the berghia nudibranch by over 4%. Needless to say both of these natural aiptasia predators will do the job. But since the peppermint shrimp won the...