Thanks for everybody's concern....my tank had already passed the wrost situation! Now no more white spots in my pair of golden knife and their eyes become crystal clear again. Other fishes condition are ok.
康仔: Actually it is a quite difficult decision at that moment: the earspot had arrivated for just few days and yet not eating anything. The white spots reappears at the golden knife, whom should have some sort of resistence . So I was quite hestitate to add copper medicine at that moment and choose adding TDC and galiac judice as a supplementary treatment....but the result...very disappointed...totally useless