Oscar & Hole in the Head

Question
QUESTION: I've had my oscar, Pete, for about a year or so and a couple months ago I put him in a 55 gallon tank and have had problems ever since. My filter came with the aquarium, the 55 gallon kit from walmart. He was fine and healthy and I got spiny eel and he got sick and eventually died from getting stuck by the heater but anyways I was told he had a rare type of fungus. I completely cleaned the tank, gravel, plants and everything several times before putting Pete back in it. BTW Pete is about 4-5" long. I recently got a Jack Dempsey, Hugh, which is about 3 inches and a Green Terror, Steve, thats about 2 inches. I know I'll need a bigger tank later. Anyway I had an algae bloom and I covered the tank and shut off the lights and it took about 10 days or so to clear up. The day I uncovered the tank I noticed Pete the oscar had a large, about half the size of a penny, spot on his head with little "dimples" in it. I was checking on him when it was covered but didn't see it until now. He also has what seems to be fin rot on his left pectoral fin. The spines are not connected and the membrane part seems kind of stringy. He still has his normal appetite too. The other 2 fish don't have signs of any of this, they actually loved the dark. Is it hole in the head and what do I do?
ANSWER: Hi Molly,
 It sounds like one of the other fish attacked Pete and they had a bit of a fight.

-- Ron
  rcoleman@cichlidresearch.com
  Cichlid Research Home Page <http://cichlidresearch.com>


---------- FOLLOW-UP ----------

QUESTION: I noticed the white has cleared up. So I don't have to worry about hole in the head than? How can I tell when it is hole in the head?

Answer
Hi Molly,
  Hole in the head looks like little round indentations in the head.  They start out about the size of a pinhead and get progressively larger.  The best way to avoid hole in the head is by doing regular weekly partial water changes (20-25% of the water in an oscar tank should be changed each and every week).

-- Ron
  rcoleman@cichlidresearch.com
  Cichlid Research Home Page <http://cichlidresearch.com>