That basically means that you do have pest anemones. There are several methods of removal, as long as you don't try to pull them out! They are called glass anemones for when they break they shatter pieces that float all around your tank and grow into new anemones. But don't worry, it isn't as bad as that sounds. You can either try to inject boiling water or lemon juice into the mouth of the anemone or pick up a product called aiptasia-x. I personally am a fan of aiptasia-x, but all 3 have been successful in the past for many that keep sw tanks.
