My main QT tank is a 55 gallon. I use this for most fish and for long term holds. My Achilles spent his first 100 days in here and my Naso also spent a lot of time since Ich was not present initially but later he got it thus he still needed 30 days at full copper + some observational time to confirm it was eliminated.
Currently I have 6 anthias in there. All 6 are eating well and have been for 3 weeks. I feed them mysis and brine both PE and smaller mysis. The brine is the enhanced kind which is mostly just for variety and in case they won't eat mysis initially. No point feeding them differently then what they will get in the display unless they are not eating, if that's the case I can go to live brine or pellets, but I rarely bother with pellets.
When I had the Achilles in the 55 I had a jeabo pump blasting a wave for him to ensure he was happy, however with all other fish I have a tunze 6065 (1700gph) in addition I have an AC 70 hob filter on the other side for slight additional flow and for the extra sponge filtration. The main filtration is the sponge filter. I usually change this after copper treatment seeded from my display's sump. Surprisingly this seems to work fine while I don't test nitrates but I'm sure they are there. I do however monitor ammonia with ammonia alert badge and it seems to remain at safe levels throughout. Looking at the sponge I sometimes see a few pods that somehow survive in it. Even after copper there usually still is one or 2.
I always keep a spare one in the sump so it's ready to go. I was actually going to use this in my second QT tank but since that tank is much smaller (20g) I can typically get away without filtration and use prime / large water changes.
Other equipment is a heater and some pvc pipe. I have large ones and small ones in there. I leave the light in the room on during the day as well as a tiny led light on the tank. Later I put other lights over the tank to help acclimate the fish to light but this is not really needed imo. There is eggcrate over the tank it would help stop but not completely prevent jumpers. So far so good but one of these days I need to make a mesh top.
Second tank is just a 20 gallon with an airpump a heater and pvc. I use this when I already have fish in the first tank. No other equipment. I keep meaning to pick up another tank so I can do tank transfer but somehow it always gets put off. I like to at least treat fish with prazipro too to ensure no internal parasites and flukes. My Achilles really had bad flukes and took several prazi treatments to eliminate them. Something that never would have been noticed at first since they are nearly invisible and the scratching only got worse in time.
I don't always fill the tanks up all the way. Especially if there are few fish in them there's no point wasting water / medications. I typically do 50 gallon water changes on my display and this is where most of the water comes from however I also use new salt water too. Typically I will start with 1 week observation followed by prazi pro. By this time Ich or anything worse will show and they can be treated with copper at this time. Of course this means longer then 30 days qt but avoids putting them straight in copper, although I suspect most (all) LFS use copper in there systems to mask diseases but not treat them. Once I get one more tank I will be happy with my fish QT but still trying to work out the coral and other invert QT procedures.
