How long does it take for Chlorine to escape?

I'm sure most of you are wondering what I am trying to accomplish here... :)

I used to keep aquariums before but I've been away from it for a while. Right now, I'm not quite in an ideal situation to begin but I'd like to start small. I know I have to move again hence I don't want to start populating big tanks yet. May be 15G long for a single species and 10G for frys. Also, the location is a big problem - warm water is very far away but cold water is very close to the tank. Hence I was thinking of simply collection cold water, let it sit over night so that it reaches to room temp, and a bit of help from the heater, I figure it will be ok. If chlorine dissipates during that time, even better! But as some of you suggested, I think I will use the prime, just to be safe. They don't cost much anyways.

I wish if I could setup tanks close to the normal tap and start using Python again, but I think I'm still about 8 months away from that environment... :( As you can see, I am desperate to get back into this hobby again. :)
 
Nothing wrong with having a strong desire to return to the hobby. It appears that you are ahead of the game already with your request for further information about your water. If you have no control over your well it is likely a good idea to keep it treated with a dechlor. I am on a private well that is on my property. No one else has access to it from my location but that does not mean someone upstream with access to the same aquifer doesn't treat their water. Being cautious is smart.
 
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