Yeh put all the media in the filter from day one, that gives it a change to accumulate the required bacteria. BTW can I suggest you just use sponge rather than the 'media' as its cheaper and will do just as good a job.
I agree, the classic range are excellent filters, just a shame you have to get separate tap connectors for it, two for my 2211 worked out almost as much as the filter!
Sam