Im pretty new but from what i know its 24 hrs to dechlorinate tap water. And lime should just make the water a bit hard. Just make sure to ph it to between 6.5 and 6.8 and it should be fine. Im sure others who have been here longer may have better opinions though lol.
Many water departments use Chloramine as well...which does not evaporate. Personally I run my water through a charcoal filter to remove it.
Like Hooha suggested...there'more to it then that. Get a water report...usually posted online. Your water is very important and partially determines what nute additions are needed. I'm talking calmag or epsom salts.
JD