dead tang

[izpowell]

bought my first fish for my newly set up tank.

I got a yellow tang three days ago and it seemed perfectly fine.

but,

when i got home from work today i noticed he was swimming awkward, and slow. and kind of swimming like sideways just drifting around. i knew he had to of been sick. then he starting laying down on his side at the bottom of the tank. then ended up dying a few hours later.

not sure why. dont know if he was just stressed or was sick

anyone know what it could be? my ammonia levels are 0, nitrites 0, and nitrates around 20

 

[hollister]

You need to list your tank specs in your profile.
Tanks age?
Size?
whats used for water flow?