I have a 29 gallon with 2 tiger oscars one bout 3 1/2" and the other 2 1/2". I did my normal weekly water change last night only about 7 gallons. Woke up this morning to both oscars with hole in the head. Any suggestions on how to fix this quickly it seems to be developing rather quick compared to other out breaks I have seen in the past. Any help would very appreciated I don't want to lose those my oscars they are some of my favorites