Thanks very much guys. Cynic it is very similar to black phantom. Can see why you might have thought this but on closer examination the tail is different and fin on black phantom is larger. Thankyou for your comment. Much appreciated.
Borderlesscott I think you have hit the nail right on the head. It looks identical in every way to X-ray tetra. Everything from fin black marking to body shape and features. Thank you so much. I can now try and get some new companions for my single x-ray. Will get onto my LFS this week. Thanks again to both of you. Regards