how long do you quarentine?

2 weeks, but every time a fish dies I add a week.

At least a month. Not sure if a week or two will make a difference. Some people don't actually qt but they're taking a chance with their stock.

Depends on the source, but usually a month minimum.

3-4 weeks

I aim for a month, usually end up at about 3 weeks. And although it really shouldn't, the length of time depends on where I get the fish from.

3 - 4 weeks.

Because we value the lives of the fish that are already in our main tanks.

Because I managed to infect almost all of my tanks with ich when I had to cut a QT time short last fall (fish had only been in qt a few days when I desperately needed the tank as a hospital tank for a peacock who got destroyed overnight). Managed to spread ich to almost every single tank, fortunately it was a mild break out, only a few spots on a couple of fish in each tank, but it was terrible to deal with all those wc and worry about losing my stock.

Also, I ran out of space this past spring but I "had" to have these L218s that came in. I figured I'd just QT them in with some juvie peacocks and haps I'd picked up at an auction. The L218s brought some kind of plague with them. I lost 5 red empress, 3 Aulonocara maylandi, 2 BNs, and 1 L218 by the end of it. The only survivors in that tank were 1 L218, 1 red empress, and 2 BNs. Those fish were quarantined for 2 months after the last death before I would try another fish in with them. Thank god I kept everything for that tank separate, I never figured out what killed them. It had to have been some virus the plecs brought in, fish would look fine and then hours later they'd be dead. It was horrible.