I’ve had the temp above 88 for about 3 days. So, probably not long enough. I have an accurate aquarium thermometer. It should be 88 or above all around because the thermometer says 90, had it is on the other corner from where the heater is.
I lost the dwarf gourami in the tank, he was bloated with an infection.
This is all because I overstocked the tank with tetras
So sorry. Yes that looks like ich/ick. I recently lost my Otocinclus and betta to the nasty stuff. Many things went wrong with my treatment. Maybe try aquarium salt or api super ich treatment or even ich x. But salt and heat if you want to stay away from medications.