I am not laughing.
Who said filter wool was not a bio-filter? Some of the mature media I picked up was filter wool and it was making a great bio-filter.
I think your lfs just wanted to sell you more kit.
It is? The thread says filter wool isn't and I did some research and a few webs say it isn't as well

I can't be sure whether mine does because my test kits are taking forever to arrive but over the 2 months, my main tank is just getting worse. Was your filter wool the loose or firm type?
I don't mind if he did sell me the ceramic rings though, they'd help filter my water more.