This past winter I had to pump out about 2 feet of excess rain water from our pool. Looking ahead to this coming fall/winter rain season, I want to collect and store some of the excess rain water (mixed with our pool water) by pumping it into a couple of 500 gallon plastic tanks. Like this one:
The ideal would be to reuse the stored water for top off starting in May. However, in order to maintain the water I would need to keep it running for 5 months with a pump or keep the tanks in a shaded area and use additives. It appears the option to reuse a few months down the line as pool top off (keep water running) is out of the question. What additives can I use to prevent algae growth or other growths for reuse in the yards (lawn, fruit trees, rose bushes, vegetables, etc)?