Why does my pool turn green so fast? The most common reason pool water turns green is due to algae growing in the water. Algae can grow rapidly, particularly in hot weather, which is why it can surprise you overnight during the warmer months. This generally comes down to an imbalance or lack of chlorine in the water.
How can I clear my green pool fast?
Will chlorine stop my pool going green? Test and Balance Water
Low Free Chlorine can cause your pool water to turn green. Always maintain Free Chlorine between 1 -4 ppm. If needed, apply the appropriate chlorine and sanitizers to restore adequate sanitizer levels.
Can too much chlorine make your pool green? The free chlorine levels might be low.
But be careful—adding too much chlorine in pool water can cause those metals to oxidize and turn the pool a different shade of green.