Lost my Flame angle and Chevron tang this morning:(

Really sorry to hear that. QT all new fish for 6 weeks in the future and you won't have to go through this again.

Lost my female clown and Henicus this morning, so it's Marine Velvet:(

You can't say that unless you have a positive ID with a microscope. Marine velvet look very different from ich and does not produce the typical white dots.

Ich can kill as fast and as strong as marine velvet, make no mistake. Different strains of ick have different virulence.

I'm borrowing a fish trap from codfather, so I can transfer all the fish to QT and cupramine, and let the display go fallow for 2 months or more

I will suggest you to get a QT, add water from your DT and let it run. For trap your fishes get a fish trap from lfs or ask if any member can lend it to you...Put your fishes in the QT and mix on they food garlic, some people said that the garlic doesn't work...but it been working for me; you can use copper too. After 8 weeks your DT will have not any ich, as they die if there is not any fish...I hope that could help you.

I sure hate reading these threads. People just keep making the same mistakes over and over and over again.... Unfortunately, some of the advice isn't the best either.

I QT new fish for a total of 3 months (not 6 weeks) and use the hyposalinity method. Have been 100% successful with that. Not only does it ensure your fish are ich free, but they get a chance to eat well and get strong before being added to the DT where they might not get a very warm welcome initially from the resident inhabitants.

The trick is to have a fully cycled QT running all the time. If you try to set one up quickly and transfer sick fish from your DT, that very often does not work. Also, it is not good enough just to observe new fish in your QT without treatment for a few weeks or even 6 weeks. They still could be carrying ich without showing symptoms and infest your DT.

And 6 weeks fallow in your DT is not long enough. Go 3 months to be sure.

And yes, ich is deadly. Many people think they have MV when their fish die, but ich kills too. I know,... as I've been through all that in the past...

I have a 90 gallon and 50 gallon that are fully cycled, they both been running with carbon, to take the cupramine out, so I'm just making sure the temp and salinity are the same before I start the transfer. The 90 has been running since the end of Dec, the 50 gallon was started in Feb

2 dead purple dottybacks this afternoon:(

You have my sympathies, for sure. I've been there and know how it feels. Hopefully you will get past this, and with the lessons learned have better success in the future.

There is a lot more to having a proper QT than just being cycled and having the same salinity (that is probably the least important). I should have said mature QT, not just cycled. That means having sufficient bio filtering capacity to handle the extra feeding and fish waste in a smaller tank. I have a canister filter with a sponge filter running all the time. Prior to use and as part of ongoing maintenance, I also change the water in the QT using DT water from changing that water.

Then after placing the fish in the QT, multiple water changes (with RODI water) are used to bring down the salinity to 1.008 - 1.009 (use a refractometer). That of course freshens up the water, too. The fish need to be at that level for at least 6 weeks since the last time you saw any ich symptoms. Any shorter, and you just wasted your time. The complete cycle for me, lowering the salinity, keeping it there (usually 2 months) and then slowly raising it, takes me a full 3 months.

Here is a good article about hypo, including many of the other benefits to your fish.
http://www.advancedaquarist.com/2007/6/fish