Well.. a little info about how the bacteria process works.
In the right conditions and temp, bacteria can double in a half hour. They will feed on the ammonia or nitrites and bring them back down. This leaves alot of bacteria w/o food. So they die off. Which means the ammonia and nitrites go back up (this takes a little while). And the cycle starts over. They will ride this roller coster untill the ammonia/nitrites reach a balance w/ the bacteria.
Knowing that, what do you think the chances are that the product you mentions can cycle a tank over night?