Betta has red spot on body

[saltypond]

My male betta has a reasonable sized red sore on his side, it looks like it could be a scrape but I'm not 100% sure.
He is in a 12L (3gal) tank and the temperature sits at a stable 25.5C (78F).
I did a 30% water change yesterday and all the water readings are fine:
GH: 60
KH: 80
PH: 6.5
NO2&3: both 0

There is a piece of driftwood as well as a few plastic plants which he has never had trouble with before.
The only new thing is that I reduced the flow of the filter because it was too strong for him.

Is this just a scrape or something more serious?
Should I be treating him with anything? He has Atison's Betta Spa in the water currently.

Photo: Imgur: The most awesome images on the Internet

 

[Delapool]

Hi, welcome to the forum and from Australia!

Is your fish improving at all?

 

[StrangelyNormal]

Your Betta's stomach looks a bit too big. You might want to feed less or split it into two meals. How much do you feed/what do you feed, out of curiosity?


Looks like he may have lost a scale.