Is this Ich or something else?

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
.

In my experience, I have had glofish tetras that had the same spotting. Took pictures and went to my LFS and they confirmed it was ich. They had me treat the tank with salt and parasite remedy. But unfortunately the fish still died. But it did not kill my other 2 glofish tetras..sorry I am not much help.

If the spots haven't spread but have gotten bigger, then it's Lymphocystis, which is a stress virus regularly carried by glass chandas (the fish in the picture).

Keep the water clean, feed the fish a variety of foods and keep the pH above 7.0 and the GH above 200ppm. You can add a bit of salt too (1 to 2 heaped tablespoons per 20 litres (5 gallons).