Here's a link to thread I started when I was dealing with velvet. Take a look through it as there is a lot of info about velvet in it and some pic.'s too. My mandarin didn't seem to be affected by the velvet but he died in QT. However with velvet all fish have to be QT'd to get the disease out of the tank, some fish have a resistance to velvet and will not show signs of it (my wrasses/CBB/mandarin) but can be carriers of the disease and give it to any new fish you add. Which is why it's important to QT and leave the display fishless for 6-8 weeks.
http://www.canreef.com/vbulletin/showthread.php?t=51938