I recently purchased a couple of dither fish from my LFS and about a week later, my tank was infested w/ ich!! 
I know there are LFS that take great care of their fish but in general, BE VERY CAREFUL WHEN PURCHASING FISH FROM YOUR LFS or simply only buy from other hobbyists.

I know there are LFS that take great care of their fish but in general, BE VERY CAREFUL WHEN PURCHASING FISH FROM YOUR LFS or simply only buy from other hobbyists.