Hi, got 4 Sterbai Corydoras in the 20% off sale at pets at home. One died within 2 days, 2 of the others have grey mold or fungus. Put the remaining 3 into a quarantine tank. Have tried API fungus cure and Warerlife Myxazin. About 10 days on, 2 still moldy, the third seems immune and has no syptoms. When in the main tank an Ember Tetra caught the fungus n died. No loses since removal of the Corys. I have had no aquarium issues of any sort in the last 4 years. Does anyone have any ideas, on how to treat these. Cheers Guava