For me a qt tank s a tank to view new fish before going into main tank. I do 4-6 weeks. If the fish has been in the tank for that time with no problems I add it to the main tank. Qt tank stays the same temp as the main tank and get its water changed the same as the main. I don’t medicate. Maybe I’m lucky. But I find most fish are stressed. Let sit in qt for a month and the stress goes away and you get them on a good eating schedule. All grow during this time and color up.
I use 2 types of filtration 1 hob and 1 powerhead with sponges attached or a sponge filter for a larger tank. I will use 2 of those choices.
My belief is that the breeder and seller have already medicated your fish so there is no reason to do it again.