They also rarely get ich. I do not qt dragonets [which they are, truly, not gobies.] I would qt a tang. But dragonets are pretty safe. Just acclimate him, transfer him in your hand and dip him midway in straight water from your tank which you will throw out. That will perhaps wash off any remaining bad stuff that could have come in from the lfs.
Note: they're slimy, and often pick up bits of aragonite on their fins or body that can look for all the world like ich. If it comes and goes, it's not ich.