that qt is way too small to treat all your fish, and you'll need to treat them all at the same time to tackle this problem. really, the DT you have would be a good size QT for these fish. that's a lot of big, aggressive fish for a 60g long term, IMO. EITHER WAY: you're going to need to get a bigger tank than a 10 gallon to treat these fish. once you get the bigger tank (you could maybe get away with a 45g, but personally i wouldnt go smaller than a 55, depending on the size of the fish you have) follow the instructions on beth's list for treating ich w/ hypo. keep in mind that not only your fish, but your DT is infected w/ the parasite.
BTW: the reason i stress the size of your QT is b/c these fish are going to be in it for a month, and considering their aggressive nature, i suggest getting a tank that will allow them to give each other space.