I thought I would pass this experience along. I have been growing herbs and vegetables in elevated tables and have noticed that when the rain waters the tables, the plants seem to thrive noticeably more. During dry weeks I have to water them via city water, that's when I started noticing the growth slowing. I suspect it the chlorine that might be stunting the growth. I installed 2 of the 55 drum rain barrels and now exclusively water using that, man what a difference!