Please explain this one

[sully08]

Originally Posted by George

How exactly did you quarantine the fish?

Quarentined him with about 30 lbs. of live rock, lots of flow and good filteration and did 10% water changes every week, always tested for ammonia and nitrites and there was never an issue

[BlueWorldAquatic]

Originally Posted by sully08

Quarentined him with about 30 lbs. of live rock, lots of flow and good filteration and did 10% water changes every week, always tested for ammonia and nitrites and there was never an issue

There is your problem, a quarentine system should be void of rock and sand.

Ich can survive on/in it when not on fish

A QT system "should" be a fresh system with places for the fish to hide, using water from the DT

Everyones QT system can vary though

[Reef Pilot]

Originally Posted by sully08

Quarentined him with about 30 lbs. of live rock, lots of flow and good filteration and did 10% water changes every week, always tested for ammonia and nitrites and there was never an issue

That's not good enough. If you did not QT with copper or do the hypo routine, you could still transfer ich to your DT.

I had this happen to me last year. I normally do the hypo routine, and have been 100% successful with that. However, last year, because I was also QTing some new inverts at the same time, I couldn't do the hypo, and just kept them all together in QT for 6 weeks.

The new fish looked fine, and there was no sign of ich, so I transferred them to my DT. About a month later, I noticed some ich in my DT (which had been clean for almost 2 years) and before long I had a full blown ich outbreak. It took me 2 more months of diligent feeding and frequent water changes before the ich ran its course and subsided. Unfortunately, I did lose 2 of my favorite fish, but all the rest survived OK. Ironically, none of the new fish got ich or showed symptoms, but they were obviously carriers. Maybe they were already immune to that strain of ich.

So just QTing fish for 6 weeks, without any treatment does not guarantee anything. My recommendation is hypo, though, not copper.

[George]

Originally Posted by sully08

Quarentined him with about 30 lbs. of live rock, lots of flow and good filteration and did 10% water changes every week, always tested for ammonia and nitrites and there was never an issue

Sounds like you just put the fish in observation rather than really proactively quarantine them. By my definition of quarantine (for marine ich), you need to use one of several proven ways of eradicating marine ich, like hypo/copper/tank transfer/chloroquine phosphate.
Since your tank is a fish only. It will be easy if you decide to treat ich on the spot.
And I can't stress enough of quarantining all your fish in general. There are stuff out there that are more dangerous than marine ich if you don't quarantine your fish. You don't want to loose all your fish, especially if you have a tank full of fish you have collected over the years.

[naesco]

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