Thanks for your reply`s well its kinda isolated on the top left of my tank & i`m guessing it will grow towards the lights so up is the way........ i`ve read that nudibranches ( slug ) like to munch on theses ffs i`ve got a slight nudibranch problem on the bottom right of my tank on a rock of button polyps keep removing one - two per night of the buttons just hope they don`t get there way up while my Xenia is taking off ............
