Velvet
 

Upon closer examination and some reading, it appears the disease my fish had or have was velvet. That would explain why my mandarin died also.

How the heck does it occur when no new fish added?
Can it be caused by stress from whatever was irritating my corals to extinction?
I have a couple fish in my display like my bangaii, that seem resistant. How do I get it out of my show tank without a period of no fish?

Lastly...:frusty:

Sorry, as far as I know, only early diagnosis and treatment with a copper based medication eliminates velvet. Had it once really bad. Bad enough I almost quit the hobby.

Velvet can come in on new frags, live rock or anything else you add to your tank. Not just on fish. Sorry to hear, im currently treating my fish for ich in a qt.

Pfft, Velvet sometimes just happens spontaneously. I've seen it in maintenance tanks that haven't had any new additions for months. I have suspicions that it can either lay dormant for extended periods or can be introduced via food. I've also noticed that a big velvet infestation can cause extreme distress to corals. Perhaps velvet is a key vector in total system (not just fish) wipeouts?

Interesting theory

Hypothesis.

That makes the most sense, even if it is a hypothesis. Its exactly my case, coincedense or not.

Ich can hide in a tank for a lot longer than a few months, as long as there are fish present. And not uncommon for hobbyists to mistake ich for velvet, especially with an aggressive outbreak. But under the right conditions, ich can indeed overcome healthy fish, and quickly wipe out most of your fish. Even moving them to a fully acclimated mature QT will likely fail unless you do it early on at the first signs of the disease.

And your correlation with velvet and corals may have more to do with poor tank conditions that affected both the fish (which made them more susceptible) and corals. Unsubstantiated theories just add to the confusion and myths with these diseases as described in the article I posted on the other thread.

In the end, prevention is still the best course with QT (or tank transfer with fish) for both corals and fish.

Doug, you said that you added corals. That's a pretty obvious smoking gun...

OK, guess I'll duck out of the discussion then. I'll go spread my wuju elsewhere. Like an Antivaccer community.