I am getting ick in my display tank. I was going to ride it out because I currently have healthy fish in QT, but I want to be able to treat my sick fish. Will a 20gallon long tank be big enough for a yellow tang, coral beauty, 3 springeri damsels, 2 clowns, a midas blenny, orchid dottyback, royal gramma, and a small watchman goby? Just until the display tank has had enough time to go fallow so about 6 weeks?