A thunderstorm will sometimes turn an outdoor swimming pool green.
It’s all about the nitrogen.
Thunderstorms have lightning and rain as well as a few resounding claps of thunder.
The flashes of lightning, apart from lighting up a night sky, create nitrogen in the atmosphere and the rain washes that nitrogen down and into your pool. Nitrogen is a plant food, and a very good one. The algae in your pool, and there are always traces in even the best maintained pool, are plants and so they thrive on the extra nitrogen that is washed down when the heavens open.
Algae are microscopic and so, when there are just a few of them, they are invisible to the human eye but feeding on the nitrogen, they bloom and multiply very quickly until there are enough to turn the pool water green and murky.
We recommend pressing the OXI Boost directly after a storm to ensure additional sanitisation and circulation in the pool.
Please see the attached Naked Water Testing for correct water balance guidelines.