Some people are more sensitive than others. I can usually detect it, and when I can, it's a serious fault and I won't want to drink it at all. Best to play it safe and get it out of there. All you need is 1/4 Campden tablet per 5 gallons of water, knocks out the chlorine instantly. It is a worthwhile investment, the $5 or whatever it costs for dang near a lifetime supply of Campden.