Happychem - that depends on the concentration of the chlorine and the surface/volume ratio along with the aeration. My 55 gallon Rubbermaids on wheels take more than 24 hours to read 0 chlorine.
Ken said:Adjust the temp at the tub faucet, sit a five-gallon bucket underneath till it's about two-thirds full, remove it, sit another one under, go dump the first one in the tank, by the time I get back to the tub, the next bucket's ready to go.
My water comes from a well in the back yard.