No, leave the media alone. Ignore the filter instructions - it's a money making scam. You only need to change media when it's literally falling to bits. All you need to do is swish the sponges in some tank water now and then (generally when the filter starts to slow down or splutter - meaning a blockage)
Do you have any fish or are you fishless cycling right now?
okay, so your doing a fish in cycle then. Keep an eye on your water parameters and be ready to do water changes if the fish start to show signs of illness or start laying on the gravel or gasping at the waters surface. There's often ammonia and nitrite problems in your situation which is the only reason I mention it.
We're here if you need anymore help
Akasha
It can take up to several weeks. If you know someone who has a long-established tank, you could ask them for some of the mature filter media to add to your tank, that way it might only take a few days. How big is your tank?