I use a mix of seachem stability Microbe-lift cycling kit (nite-out/special blend.) The yellow can of mardel bacteria is a good idea too. That combination gets the job done fast and well for me.
Another that that can help is algone. You just put it in your filter! Doesn't get much easier that that. It's an enzyme.
Oh and once again just my opinion but dont use an undergravel filter. I have never found them to be worth any amount of money. I use 2 hang on wall filters since they are good for moving water and adding oxygen.