Is this Ich or something else?

[Jonatheber]

I have a freshwater livebearer 46 gallon tank. The water is fine, and I do weekly 20% water changes. About a month ago I noticed that two of my three painted glass tetras have white spots like you see in the picture. I wasn't sure what it was (new tank owner here) so I didn't do anything. About 2 weeks ago, I did some googling and saw maybe it was ich so I added 1 tbs aquarium salt/three gallons of water. Today, the same fish have the same raised spots (there is on on this fin that looks like a really angry pimple it is so large). There are NO other fish in the tank with ANY spots.

 

[Delapool]

Doesn’t sound like it from the time span - any flashing at all?

Sometimes can get pimples which have a centre parasite (not as aggressively spreading as white spot) or bacterial infection.