can someone help my fish are all dying ive got a 42 gallon tank i used to have 45 fish in it i went on holiday for a week came back home a week ago and ive got 20 fish left i noticed that that most of them had white spot on them i treated the tank lost a few more fish and then it seemed ok i bought some more fish the next day one was dead and the others have white spot again the treatment doesnt seem to be working and is it right that you have to remove the fluval filters while treating the fish