Bleeding Heart Tetra Has Weird Spot [Pic]

[gdoggy1678]

Hey guys my tank has been running for about 2 months with fish and today have discovered this fish with a weird discoloration. Its not on his skin but seems to be internal. His behavior is also very eratic and twitchy and scares the other fish. My tank has 8 bleeding heart terta, 6 peppered corys and 2 Bolivian rams and no other fish show any type of familiar symptom. I change my water about 50% every week and my temp is kept at 76-77 Degress ferenhight also my tank size is 29 gallons (120L)
1. Water parameters. (ammonia, nitrate, nitrite, PH, temp', Hardness etc)
Amm. 0ppm
Nitrite 0ppm
nitrate 10ppm
ph 8 Temp 76 77 F

2. A full description of the fishes symptoms.
Abnormal dark/white spot also erratic swimming
3. How often you do water changes and how much.
50% weekly
4. Any chemicals and treatments you add to the water.
No
5. What tank mates are in the tank.
8 Bleeding Hearts, 6 corys, 2 bolivian rams

6. Tank size.
29 gal 120L
7. Finally Have you recently added any new fish?
No

 

[gdoggy1678]

Been doing some looking around and it seems to maybe resemble Pleistophora or Neon tetra disease. What do you guys think? Unfortunately i dont have a hospital tank but i dont want my other fish to get infected. Input please?

I Dont want to but im thinking about euthanizing the poor guy.