Brown patch on golden dojo's head

[Lighting]

This has been around several months and I haven't noticed any strange behaviour, but I don't think that it was there when I got him. Could this be an infection?

[Diana]

My first thought was a burn from the fish lying against the heater.
But if it has been there for several months I do not think that is it. A burn would heal faster than that.

[Lighting]

My first thought was a burn from the fish lying against the heater.
But if it has been there for several months I do not think that is it. A burn would heal faster than that.

He's in an unheated freshwater tank so this is not possible. ^-^'

[Diana]

Is it changing? Growing larger?
Has this fish always had this dark patch?

[Lighting]

I haven't noticed any changes, but honestly I can't remember for sure if he always had it. ^-^' I've had him for many years now and i'm pretty sure he didn't have it when I got him but he has had this same patch for at least a while.