Q:

Identifying sound from pulleys to replace appropriate part - 2006 Altima 3.5

By watching the video I've taken, can you tell what component is causing this grinding noise? Someone suggested it might be the harmonic stabilizer. 
Known issues

Discovered low power steering reservoir, haven't noticed level go down since filling
Power steering fluid found under car
Recharged AC after the winter, isn't as cold as it used to be
Increasing RPM will increase pitch of grinding noise
The ticking noise is probably a timing chain tensor I have to replace. 

Tested good

Turning wheel, to test power steering, doesn't change the sound
Not over heating, indicating good water pump?
Car voltage tested good, indicating good alternator and battery 

Pulley diagram

A:

If you don't have a stethoscope or a screw driver or similar that you can use as one. Pull the belt off, put some tension on one pulley at a time and spin them by hand any roughness indicates bearing/bushing failure. 
You can probably rule out the compressor pulley as the noise doesn't change as the clutch engages. Idler pulleys are the most likely to fail first. A water pump has a deeper sound when they go bad and usually leak. It doesn't really sound like a harmonic balancer either, usually when they go bad the rubber will separate and cause a screeching sound. 
It will probably end up being the alternator or idler pulley. 

