Betta fish color change help

[SRS]

Hi all, I was wondering if someone could help me figure out what’s going on with my betta fish. I’ve had him since May, he’s in a 5gal filtered tank heated to 80 degrees. In the last week or so he has started having some color changes with his scales getting grey/pale around his face and sides, looks symmetrical on both sides. He’s still eating but seems (maybe?) a bit less active than usual. Haven’t noticed any changes to his tail or fins. I checked the water parameters:
pH 7.5, nitrate and nitrite 0, GH and KH 180. Ammonia 0.
Would the hardness of the water be of major concern?

Could this be something like Columnaris or a fungal infection?

I attached a couple of pics. First pic is what he looks like now, second is a couple of weeks ago for comparison.

 

[jkkgron2]

Hardness is fine. That does remind me of a bacterial infection or columnaris. Any new things that you added to the tank?

 

[SRS]

No new tank mates. There are a couple of nerites but they’ve always been there.

 

[jkkgron2]

No new tank mates. There are a couple of nerites but they’ve always been there.

Any new plants?

 

[SRS]

No, the only real plant is a Marimo moss ball

 

[UnknownUser]

It also reminds me of columnaris. Any stressful events in his life lately? Could be as simple as someone tapping his tank or missing a water change.

 

[SRS]

I did move a couple months ago, so did a 100% water change to move the tank. I do 25% weekly water changes normally. Possibly delayed effects from that?

 

[UnknownUser]

I did move a couple months ago, so did a 100% water change to move the tank. I do 25% weekly water changes normally. Possibly delayed effects from that?

Columnaris is pretty immediate, so that wouldn’t be it. How long has it been spreading? Fungal would likely respond to a salt treatment, but I’m not sure how bettas handle salt. It’d be my first choice though, if the issue isn’t spreading fast. Could also add some indian almond leaves. Second choice would have to be meds, but since we don’t know what it is, it’d be a shot in the dark and possibly kill him faster because meds are hard on the system.

 

[SRS]

Thanks for the input! I think the change has taken place over about a week or so. I will try some Indian almond leaves and aquarium salt first. I also have kanaplex and jungle fungus clear on hand that I might try if not getting any better.