[terryp01]

Ah, the topic of the day. I would ALWAYS suggest to quarantine a fish regardless of where you get them from. The stress of catching a fish and relocating is enough to stress them out and they can get ill from your existing tank. Most LFS get a fish and sell the same week they receive. There are exceptions but the cost of holding fish and the risk of losses is too expensive to do so.

Just because the tanks are treated with copper doesn't mean it has killed the 'disease'. If you read the instructions on copper they usually require you to maintain a level of X for X number of days. If the LFS gets the fish today and sells in the next couple the bet is the parasites have not been killed.

It also allows you to make sure the fish is eating prior to adding to your tank. Hard to catch them once they are in.

I quarantine all of my fish for two weeks regardless of how long they were in the store, etc.

Duss