danedodger
Member
It could also show symptoms of illness, like the spots you saw, simply from the stress of being moved from one tank into your own. Have you had any fish with this problem before? Have you ever dumped the whole bag, fish and water, into your tank after acclimating? The disease has to be present either in your tank or the LFS tank then the fish's immune system goes down a bit for one reason or another (usually something stressing them) and the illness takes advantage of the situation. If he was ok in their system for 2 weeks and got sick within 3 days of being in yours my money would be on your tank is hosting the parasites (most fish in LFS go through a heckova lot more stress, temp variations, poor water quality, etc. in shipping to the LFS than moving from the LFS to a home tank so if the parasites are hosting in their tanks it would be a lot more likely that he'd have shown signs of it in the store). It's an even stronger bet considering that you've had such trouble with tangs in the past. Some of the parasites probably fell off the fish that were infected in the past and are now hosting in your tank waiting for a fish in your own tank with a weakened immune system.
