Below is the amount of rainwater I used in 2017. The system volume total is about 4000 gallons, so it’s kind of interesting that it is somewhat close to the total used all year long. This was the first year of using only rainwater. I decided to collect rainwater to illustrate the amount used and, more importantly, be more water efficient instead of pulling from our well. The sodium content of our well water is about 240ppm of Na and that is way too high. The plants seem to be much happier now that it is down to about 25ppm. I may start adding some well water again to supplement Ca, but will keep an eye on the Na.