i woild definately take off the xenia. because soon the xenia will grow larger and will compete for light with the maxima and unfortunately the maxima will lose if the xenia is not removed. try to get your nail and get as close as you can to the base of the xenia and GET ALL THE XENIA TISSUE OFF THE SHELL! even a small amount of left behind tissue will regenerate and just grow again. make sure to get it off asap before it starts growing larger.
Hope this helped, Andrew