Be careful,
Enter into the regime very slowly and be aware that you can NOT in any way shape or form stop once you start. Essentially what you are doing is getting bacteria to grow to an excess. This results in two things happening- both of which removes nitrates.
Firstly, the aerobic bacteria will assimilate nitrates into their cells as part of the protein they contain. They will grow very rapidly and will deplete the oxygen in the water as they grow. - thats the main issue with nitrate removal via carbon dosing.
Second, the anaerobes will convert more nitrate to nitrogen and nitrous oxide, which will enter the water in the tank. Nitrogen will escape but nitrous oxide, in large quantity will begin to have a delterious effect.
this is why you have to increase slowly.
Now- as to why you can not stop.
the moment you quit all that extra bacteria will die. The result will be massive pollution of the tank and the consequences may be a total wipeout.
So, to ensure you are removing as much nitrate as possible- skim agressively. Ensure you get as much oxygenation as possible and if you do decide to stop, decrease as slowly as you increased.
its doable- and works well- but just beware.
Also- figure what the problem is in the first place if you can. Something is maing nitrtaes faster than your system can cope.
Paul.