To be honest, it is quite hard to put an exact time on when you should see results. I would recommend treating with the Kanaplex every other day up to 7 days. If the infection is as severe as you say, then it may take multiple doses before you see any improvement. Also during this time be sure that you are maintaining high water quality, as poor water quality is usually directly related with bacterial infections. You should remove all chemical filtration when dosing medications to ensure 100% efficiency.