Missing Scales vs. HITH (Follow-up)

Question

A Blurry Picture with   QUESTION: A couple of days ago I noticed what appear to be a couple of scales missing from the back of my Oscar's head.  I suspect he bashed himself on a rock, but I am wondering if it could be hole in the head.  The picture isn't great (he kept turning around on me) but I think you can get a good idea from it - it looks like 3 scales are missing.

I've had my him for about 6 months now, and he is about 8.5 inches (I'm guessing he was pretty young when we got him, at only a couple of inches in size).  Until a few weeks ago he shared the tank with 2 4-inch Plecostomus.  One of them died (possibly swim bladder issues - he died within 24 hours of when we noticed him looking oddly bloated and uninterested in food) but the Oscar and Pleco 2 seem fine (Pleco 2 was stressed for a few days, but pulled through).  I have been having issues with Nitrates for the past couple months - I read that the best bet was to do a ten percent water change daily.  I was worried that would be too much, so I have been doing 10% every two days, and that seems to be under control.  I feed my Oscar Cichlid sticks and I put Aquasafe and EasyBalance w/ Nitraban in his water when I change it.  He seems to be just as healthy as ever, normal appetite, and he's learning to swim backwards through the hole in his rock - a possible source for the missing scales.  So should I worry on not?

ANSWER: Hi Emily,
 That is not hole in the head.   It easily could be mechanical damage as you suggest and the scales will likely grow back.

 Note: you cannot do too many partial water changes.  You could change 10% of the water twice a day and that still wouldn't be too much.  
You shouldn't change more than about 50% of the water at once and in general I recommend changing a max of about 25% at one time to avoid shocking the fish.

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


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


Healing?   QUESTION: Hi Ron -
A few weeks ago I asked you about some missing scales on my Oscar's back.  Guess what?  We're still worried about him.  His appetite/ energy level/ etc. are still all normal (although he seems particularly ferocious lately whenever we feed him).  But now that spot on his back is larger and pinker.  Scar tissue maybe?  Is he regrowing his scales?  Or is it something to be concerned about?  New photo attached.

Thanks,
Emily

Answer
Hi Emily,
  Hmmm..  fish generally don't grow scar tissue.  They simply regrow the missing scales.  Should you be concerned?  A little.  It MAY be that he haa a bacterial infection around the wound.  I am reluctant to use antibiotics on fish in most cases, but this might be one time where you should consider it.  Personally, I wouldn't do anything for a while longer and see how it develops.  If it gets worse over the next couple of weeks, then consider antibiotics.

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