Yep, I definitely keep the water quality high in my QTs.
I do daily 15% water changes, and about 30 minutes after I feed I siphon all the uneaten food off the bottom. Ammonia/nitrate/nitrite are all 0, pH is about 8.1, salinity is 1.024.
I havent tried any live food yet, but I'm thinking I might pick some up tonight to try. Sucks, I hate feeding something live food and then having to wean it off that. But if it saves the fish, then great.
Well I'm not putting my Gold heart into the main tank for a while yet, I had an ich outbreak in there two weeks ago and I'm letting it remain fallow for another 2 months before I put fish in, so hopefully this little guy learns to eat while in QT.