Tinfoil barbs are freaking out

[Mr. Bubbles]

I have two tinfoil barbs (8in.) and they are both missing some scales. They are also darting alot. Sometimes, they will swoop down sideways all wierd like. Thats the only symptoms I could think of. The water conditions are:
Nitrate-60 ppm,
Nitrite-.5ppm,
GH-120 ppm,
PH-6.5 ppm,
KH-60ppm
Im pretty sure its not ich. I put ammo lock, stress coat, and melafix in my tank.

 

[kodzzz]

Try adding some black water extract to calm the fish down.

 

[jerome9731]

how long have they been in the tank? any other fishes beside them?

 

[Mr. Bubbles]

there is a black ghost knife and a pleco. They have been in there for about 2 years