Possible Disease or Fugus on my Oscar Fish?

[Soah656]

Have you tested your water?

Yes

If yes, what is your ammonia?

0

If yes, what is your nitrite?

0

If yes, what is your nitrate?

0

If I did not test my water...

1. ...I recognize that I will likely be asked to do a test, and that water tests are critical for solving freshwater health problems.

Do you do water changes?

Yes

What percentage of water do you change?

61-70%

How frequently do you change your water?

Every week

If I do not change my water...

1. ...I recognize that I will likely be recommended to do a water change, and water changes are critical for preventing future freshwater health problems.

As the post title says so..
My oscar fish is a little over a year old now. 9 to 10inchs. I haven't had any problems except HTHD a few months back.. I believe i was using to much carbon. I have stopped using carbon completely, treated him with api general cure and went full biological. Needless to say, one week later he responded very well to the treatment, cured up very nicely after a while, and tank is running great water chemistry wise. I'm running fluval 407 cannister on 60g quarter-cylinder corner tank. I plan on upgrading him very soon. I stay on top of lots water changes, I'm trying to get best colors as possible with him. I do about 20g every few days more or less, flush the filter out every couple weeks and supplement with aquarium salt 4 tablespoons once sometimes twice a week.The fish love our well water and I'm grateful for having our well. I have him with a common pleco. The fish aren't acting up or doing anything that would cause concern. My only concern is this black spot on the left side of his face that comes and goes with his coloring. I've taken some pictures. Is this some kind of fungus or is it something that I can possibly help get rid of. I think it's part of his coloring but I don't like it lol anywayz let me know what you think. Any help is very appreciated. Thanks















PS-his name is Ralph. Hint the R figure on his tail ?

 

[kno4te]

Doesn’t look like fungus. Could be stress making the color change. I’d suggest not adding any more salt. Clean out the filters but once a month. Use old tank water to clean the filters. Are u adding any dechlorinator to the tank? Ur tank isn’t cycled with all 0s for the testing results.

 

[duanes]

It looks to me like the onset of HLLE (hole in the head) due to too few water changes and elevated nitrate, in a smallish tank.
Although meds could help...... that's not addressing the cause........ and without addressing the cause, HLLE always returns, even with the use of meds.