How to stop your hair from turning green in chlorine

• Use a leave-in conditioner: Before going to the pool, apply a leave-in conditioner all over your hair. Copper will have a harder time attaching to your hair since the conditioner is coating the hair shaft. The conditioner will also make your hair easier to wash out after swimming.
• Wear a swim cap: While it might not be the most fashionable accessory, wearing a swim cap will prevent your blonde hair from turning green. As a bonus, it will also keep chlorine from drying out your hair.
• Get your hair wet: Wetting your hair before going into the pool may prevent the chlorine and copper from sticking as tightly to your hair.
• Don’t use copper-based algaecides: If your hair turns green from swimming in your pool at home, don’t use a copper-based product to kill your algae. 
• Wash your hair immediately: As soon as you get out of the pool, wash your hair immediately with shampoo to prevent copper build-up.