Scales on betta's head turning bronze?

[alli789]

Hello! I noticed last night that my betta seems to have some scales on his head turning a brownish bronze color. I just wanted to make sure that nothing is wrong.

Background: I've had him for 6 months. When I got him he had a white head and some white mixed in on his back, so I actually thought he was a koi. However, within a week of good care, almost all the white disappeared and he's been dark blue with a few light blue scales dotted throughout for the entire time I've had him. His lighter scales don't seem to ever change locations. So I'd kinda ruled out that he's a koi, but I wanted to mention it in case these new colors could just be a koi gene.

 

He appears to have the tiniest bit of loose skin around his bronze scales (like a really small amount. It's hard to even notice). I just rescaped my previously all silk planted tank and replaced everything with dragon stone and live plants, so maybe he just scraped himself a little while exploring? (all the plants were quarantined for a month and alum dipped.) This morning, he also has some dangling stringy poop (just a short bit). It's brown, not white. He doesn't appear to be bloated at all. He's acting totally normal, active, eating. 

So that's what's going on. Hopefully it's nothing but I wanted to check! The bronze doesn't look like velvet, it looks like scales to me. I only see it on his head, not his gills or the other half of his body. Nothing on his fins. Oh, he does have some missing pieces of his fins that was from fin rot, but his fin rot seems to be gone after treating it. His fins grew in about half way before kinda stopping, but they haven't gotten worse again, so I think that might just be how his fins will be now. 

 

Tank:

10 gallon

Heated at 79 degrees F, filtered, fully cycled

Fully planted with anubias and java fern

No tank mates

No ammonia or nitrites. Nitrates are around 10-20. 

Weekly water changes, usually 30-40%

[Daniel]

It happens, fish can change color as they age. If it were my fish I wouldn't be worried.

[Maggie]

My galaxy koi plakat (red, white and blue) has turned steadily more blue in the past 5 weeks.