Puffer has pimples

Can you pop it?
 
There is nothing to suggest there is a water problem. Nothing has changed, Like I said this puffer had one small white pimple for many months and then in just a few days he has them all over his head and a few on his belly. When I got home today he looks a little better but there are still some pimples.
Just FYI, water is:
PH 6.8 (6.0 with co2)
KH-40ppm
GH-60ppm
nitrite/ammonia- 0
nitrate 10-20
dosing- phosphate, potassium, nitro, iron and trace elements.
Temp- 78°
 
I dont know about dwarfs... but it isnt his spines is it? Most puffers will have little dots that I suppose look like ick but its actually there spikes they can deploy in self defense. Here is a pic of one of mine, note all the little dots...

fig8puffer_12.JPG
 
No, the DPs do have some small little dot randomly scattered across their bodies but these are raised. I'm going to have a picture later tonight.
 
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