Oscar problem?

[kno4te]

Would that usually occur due to fighting with other fish or running into things?

Can be from both.

 

[Hank82]

Occasionally my oscars get some white specks (not ich-larger specks or patches/marks) on their pects. My routine for anything that is concerning but not necessarily full blown disease:
1. Large water changes. Twice a week.
2. Add some salt
3. Add some StressGuard
4. Keep temp below 80.
5. Monitor

In fact, I do the above anyway as usual practice. Except the salt and stressguard. Diet is also extremely important. Nutrients, minerals and vitamins a must.

I do 3 water changes a week

How much salt? I have a 112 gallon tank

Temp is 78

I like starring at them frequently

 

[LBDave]

I do 3 water changes a week

How much salt? I have a 112 gallon tank

Temp is 78

I like starring at them frequently

I use salt a bit more moderately than others suggest. Especially if I am not really targeting a specific disease so to speak.
So I use about 1 to 1.5 cups of non-iodized table salt per 100 gal.
Something in that range. Like I say sometimes I see white dots or specs on their pecs. It ends up going away. Tissue damage from hitting something etc. ? Not sure.
Lately I have been changing about 60-70% of the tank water and almost all the sump water. I clean the socks and filter pads and vac the substrate. It's a lot of work but so far I enjoy it.
I like to watch all my fish too. When I take my glasses off it's like using a microscope.

And as far as fighting, if the oscars are fighting among themselves you would most likely see marks around the mouth.

One thing I have mentioned on other posts is that fish can build up a collection of slime coat at injured areas (whitish appearance). It's possible this is what you are seeing if the fin otherwise is operating normally. Most fish keepers worry that the white is a fungus or even a bacterial problem (if white on the body). So concern is good, just need to monitor.
I am not an expert in any sense, just relating my own experiences.

 

[pops]

I would personally keep the water pristine. nothing else. given good diet and good water Oscars are pretty tuff.