Single white spot

[Survive]

My glowlight tetra has this spot I noticed today. I not been around much so I don’t completely know if it’s new but I feel like it has gotten bigger since I took this picture a few hours ago. It looks way too big to be ick and I am not yet familiar with much else that would look like this if anyone has any ideas. Much appreciated!

 

[Aiken Drum]

That looks like a fungal infection. Can you quarantine the fish to treat it?

 

[Survive]

Thank you. Unfortunately he died overnight. He was completely white when I found him so it spread quick. None of my other fish seem to have any issues. Should I do anything for them? I added some aquarium salt when I took him out. I also saved him in a baggie for when I can go to the pet store so maybe they will have an idea too. I'm ordering a quarantine tank in case another fish gets something (I'd just go buy it but I'm sick and not trying to spread germs).

If it helps it seems that sometime between 2 days ago-ish and today a nitrogen and nitrite spike eliminated itself for whatever reason. I'm glad for the community but I'm not sure if that could have anything to do with it.