Betta with white marks

[ElenaSp]

Hello!! I noticed a few days ago this white, shiny spot on my bettas head. It looks lime he injured himself but then I saw another small white shiny spot on his side. I've been using fish recover from brightwell aquatics for 6 days but I don't see any changes.
Tank: 4.5g
Heater: No
Filter: Yes
Ammonia: 0
NO2: 0
NO3: 0
PH: 6.5
Tank maintenance: Vaccum weekly 40% of the water. (2 times a week now that I noticed these symptomps)
Food: JBL flakes and ocean nutrition pellets.
Quantity: 3-4 pellets and a couple of flakes (I feed twice a day)
His behaviour has not changed.
He is still eating
Should I meducate with sth else or wait it out?

 

[Archerfish]

I'm new here so forgive if I violate protocol. I have (judiciously) used aquarium/sea salt with success in your situation. The International Betta Congress is in my opinion, preeminent. Here is a link that might be useful: https://www.ibcbettas.org/aquarium-salt-the-healthy-preventative-v-2-0/