Ok, so I constantly see this conversation about water and Chlorine or Chloramine and it seems many people really have no clue about their tap water and if they have Chlorine or Chloramine in their local waters. Many people state that they use tap water for watering their plants, others state you should not use tap water due to chlorine and others say you can use tap water if you fill your water container and let it sit out at least 24 hours. The 24 hour or longer sit period is to allow Chlorine to evaporate, which is very true it will do so in a period of 24-36 hours. However sitting your tap water out in the open for 24-36 or even longer will not let Chloramine evaporate. Actually one of the only techniques for removing Chloramine from tap water is to run the water through an extensive carbon filter (to remove the chlorine molecule) followed by a reverse osmosis or cation filter (to remove the ammonia) is necessary. Chlorine on the other hand can easily be removed water tap water, letting sit out, running through a simple carbon filter, or using any aquarium based Chlorine remover. How do you tell if you have chlorine or chloramine in your tap water? Well there are many ways to find out, including asking your local water company, another route is to visit http://www.ewg.org/tap-water/home ... then enter your zip code into the Whats in your water? box located on the right hand side. You will then see a page listing all the elements in your tap water. You will either have chlorine listed or a chloramine. You can also read much more into chloramine at: http://chloramine.org/chloraminefacts.htm Chlorine or Chloramine are not bad for your plants, they will not kill your plants. What Chlorine does do is actually effect the micro's in your soil. There are many benefits though to using tap water to water and feed your plants. chlorine in your tap water can actually help reduce or eliminate many root or soil related diseases and illnesses, but does kill many micro's in soil. It is a catch 22 really when you really think about it, but be assured majority of all tap water in the US is safe to use on plants with doing nothing more than a PH up or down and many times PH of water coming out of a tap is great for soil grows. Not all locations, so do please check your tap water for PH and adjust if necessary. I hope this information helps anyone out there, I hope the noted web sites above give some great information to those that use it. Good luck with all your grows!