Sorry I posted b4 I read the second page... first time for me on that xD
To add a little bit to this for ya then, be patient, once your ammonia and nitrites dwindle down close to zero, then you can start to do regular water changes to dilute the nitrates.
Nitrates don't go away on their own, there are only 2 ways to get rid of them; Water changes or having some type of Algae (Macro or Micro) using them up; such as a ball of chaeto or an algae scrubber.
Water changes only dilutes the nitrates, so if you have 80ppm nitrates and do a 25% water change your still going to have 45-50ppm after the water change. Slowly do water changes and I wouldn't do more than 30% at a time, and give it time for your bacteria populations to replenish after a water change (5-7days?)... once your nitrates get down around 20ppm you can start looking for stuff to add to your tank (CUC prolly first) then wait at least a week in between adding things to your tank to prevent any ammonia spikes.