Ok, it's definitely a Majano. They have a poisonous sting. It's exactly like this one that has been ID'd/confirmed as Majano. " These small anemones are a frequently encountered pest anemone. They are very similar to Aiptasia anemones. If left unchecked they could soon reach plague proportions in the tank. Their sting is very potent and should be eradicated as soon as possible. Joes Juice is reported to work and is simply to apply using a syringe. If you can remove the rock then application of hot soldering iron can also be tried. A mixture of kalk can also work, if applied with a syringe. "