It is one bloodfin terra with a large white/pink bump on his mouth. A few other of the tetras have a similar things on their mouth but none as big as this one. It seems to be getting worse.
Ammonia-0
Nitrite-0
Nitrates-10
They are in a 55 gallon aquarium that has been set up for at least 3 months. The tetras are around 2 weeks old. I had one tetra die. I'm not sure why.