What is this!

[zenyoungkoh]

I found this white pimple-like growth on my minnow's head. It also has a similar growth on its underside.


I have 0 ammonia, nitrites. I do 50% water change every week.
Any idea what it is?

 

[zenyoungkoh]

I suspect it being a leech. Its not just a pimple like growth, it seems to have a resemblance to a curl up worm creature.