WOW, this thread turned out great, what a soap opera! (No offense ntracy).
I just need to say something here, I'm gonna get criticized for it but sorry it's just my opinion...
I don't run a QT, I don't feel it's necessary for the 'average aquarist' to go through all these die-hard measures. If you're gung-ho and have 20 tanks with conditions more sterile than your own kitchen table than I can say "of course you'd have a QT" and you should. But I truly believe it is a huge burden to set one up properly for the average beginner and to safely perform advanced 'hospital' treatment on fish. I don't think this whole pushing everyone to use a QT just because you decide to is the 'best suited option' for everyone.
I know all the benefits of a QT and YES, of course, a QT is a great step to the acclimation process and provides a great place to treat fish. But for most people, (as in people who don't live in a fish store), who just have a nice simple 'living room tank', I TRULY believe a QT is not the best option unless they are decisive on having one as is on their own.
I really really really hate to say this.... but, I saw this coming. To have all of your fish die over this process is because of all the stress they underwent over the last few weeks. Ntracy, hats off to you, you did a fantastic job with 'trying to do the right thing' and listening almost to a "T" with what the advanced people on here coached you with. I know a lot of this is all new to you and you may not have made the right decisions with stocking the tank etc. but I really think you had good intentions in mind and were just trying to listen to all the advice in this big mess of confusion. One thing you gotta remember though is this is a just a Board with people's opinions, most people have LOTS of experience which is great, some people are clueless just posting something just to post, but take it for what its worth. If you don't feel like you want to do something, or want to try another way then do what you feel. 'There's more than 1 way to skin a cat', that applies to this hobby as well and I've seen things done that people said "can never be done, no way" and I've seen people do things successfully that I've tried and wasn't successful with. You need to just figure out what works for YOU. Develop your own methods and techniques, take everyones advice for a good base to start with but then you'll learn to adjust to what suits you.
No matter what you do, people are always gonna criticize you. Someone always has their 2-cents to throw into something. Even if you did everything 100% correct, someone is always going to be trying to think of something additional they can critique on. Thats just life, with opinions a dime a dozen.
Like I said earlier, I saw this coming, way back when you posted that you went to Wal-Mart and got all the stuff and were going to start the hypo.
I'm sure you know all about ick now, Tangs are obviously Ick-Magnets and are usually the problem for everyones tank. One thing though you can always try (I've successfully done it, but like I said, I can't speak for others experiences), is to do "nothing". Ich attacks 'weak' fish, if your fish are healthy and happy they will naturally repel Ich.
The theory here is as follows: Your fish breaks out with Ich. Usually just after adding him or making some other big change to your tank. Well trying to catch all of your fish is going to put a huge stress on your whole tank. Now not just the 1 fish has it, but it starts to spread because the other fish got super stressed and their immune was down. Once you finally get them all into QT you'll probably realize multiple fish have ich now. Then you further stress them out by screwing with all kinds of additional levels etc.. Before you know it fish are dying, quite rapidly at that. (This applies to your case ntracy).
If you 'do nothing' you have to figure there is a little risk involved but worth it in my opinion for the average to beginner hobbyist. All you need to do is make sure your fish are as healthy and happy as possible. Meaning food, water quality, temperature, SG, light and no stress from tankmates. The ich will begin to fall-off the sick fish, as you know, during the stages and enter the water column free-floating. Well as your sick fish begins to get healthy and avoids stress, it starts fighting off the ick more. The ick falls off and isn't able to attach itself again because the fish is beginning to repel it. After a few weeks it'll get to the point where the fish is back to normal condition and healthy enough to fight off ick and prevent re-infestation. Your other fish won't be jeopardized because of all the QT stress and the sick fish won't be either.
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