Can you help me figure this out?

[FriendlyLoach]

I know that what is happening to my neon tetras is common. They have these white bumps that have slowly grew and spread from fish to fish. I see people with this all over the internet. I was wondering what peoples experience is with this and if you know a cure. I tried treating them with salt, paracleanse, and E.M erythromycin and nothing helped. I already had to euthanize two of my fish from it. 

Thank You!

[Colu]

If maracyn has not worked try maracyn 2  one treats gram positive and one treats gram negative bacterial infection  its bacterial or viral infection looking at pictures add aquarium salt one table spoon for 2gallons with maracyn 2 salt will damage you plants at that level

Edited January 1, 2021 by Colu

[Hobbit]

I don’t have anything to add but I also have a tetra with two spots like this on him at the moment. Maracyn, salt (3 tbsp/5gal), and melafix haven’t touched it. I’m going to try ich-x next (I think it’s a long shot but I’m trying to treat some fin rot too) and if that doesn’t work I’ll try maracyn 2 like @Colu suggested. Let me know if you make any discoveries!