Sorry for all the issues you are having, especially when starting up...very deflating.
I am not an expert by any means nor claim to be. I've been in this addictive hobby for about 6 years and still come across issues every now and then. Don't give up, you will have fish, one day, in your DT!
I set up a qt not too long ago about 3 months ago. I did my research on the RC forum. I suggest you check it out. It helped me out, immensely.
There's several methods they mention, I believe:
TTM & dosing with medication. I have not dosed any medication, as of yet. Still in observation mode.
TTM, correct me if I'm wrong people, stands for tank transfer method. Which, if I remember correctly, means observing said fish(s) in qt for about 30 days or more then transferring to another tank and observe some more for another period of time and if there are no signs of disease/pests/parasites, then you can add to DT.
Other method is to dose qt with medication only when there are visible signs. At least that's what they mentioned. Remember, first 30 days or more, is just for observation. Checking for any signs of ich or what have you. If no signs, they say, no meds. Kinda like, if it ain't broke don't fix it. I haven't dosed anything in my qt since start up. I observed for 2 months with no issues and into a DT they went. So far so good. Currently have a moorish idol in observation as we speak.
Someone on here has a different method for adding new fish to their display, dipping in 63ppm peroxide solution for about 30 mins. then toss them in the DT. He swears by it, even done it petco fish.
I probably didn't help you very much, if any at all. Again, no expert here. Just a reefer striving for success in this hobby.
I highly suggest reading that thread on RC, it helped me immensely. Don't give up...
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