Newly cycled (1 week) and I added some fish. Bentos tetras and harlequin rasboras. Water has been at 78F, 0 amm, 0 nitrite, 10 nitrate, ph 7.6 for the entire time. A few rasboras quickly developed fungus on their backs (they didn't look great in the store), so I moved all of them to a QT and...