My tank has been running about 9 months so far with no problem. 4 days ago, I notices that my blue tang get ich so I decided to set up QT and let it run about 2 days. Today I move all my fish from DT to QT and thing happen liek you see in the image. Here is how I add cupramine to ly 21 gallons tank
10.5 us gallon=20drops and redose another 20 drops after 48hour. So my tank needs 80drops totally to hit the number at the end. But I want to do slowly so I added 20 drops each day for 4 days. Today is 1st day and fish dying. Can Anyone explain what happen so I can avoid on the future. Thank you all