You were entertaining friends, and your pool turned green overnight. Don't panic: green water can be restored—often in 24 to 48 hours—if you follow the correct steps.

In short: first balance the pH, then shock treat, add an algaecide, filter continuously, then clarify. Don't guess the quantities: test your water and follow the recipe adapted to your pool.

Understanding: why your pool is green

Green water is almost always a story of algae overpowering your disinfectant. After a storm, a heatwave, or a long winter, chlorine levels drop, algae awaken, and the water turns from clear to green in a few hours. The darker the color, the more advanced the proliferation—but in almost all cases, it's fixable.

Diagnose your water in 2 minutes

Before adding anything, you need to know what your water truly needs. Test your water with Barracuda: you get a clear reading (pH, alkalinity, chlorine) and the exact list of products to use, in the correct order. A question on a summer evening? Our expert assistant Barry can guide you anytime.

Action: the step-by-step recipe

1. Balance pH and alkalinity. An incorrectly adjusted pH prevents shock treatment from working effectively. Adjust them first with balancing products.
2. Shock treatment. Perform a chlorine shock treatment, preferably in the evening, with filtration running.
3. Algaecide. Add an algaecide once the shock has dissipated, to finish the job and prevent regrowth.
4. Filter and clarify. Let the filtration run continuously and use a clarifier to clump particles together and restore clear water.

Always respect the doses and times indicated on each product label — or, even simpler, let the Barracuda Water Analyzer calculate the exact recipe for your pool's volume.

How long to get clear water back?

With light green water, often allow 24 to 48 hours. For dark green or opaque water, plan for a few days and clean the filter along the way. Continuous filtration is your best ally: it removes dead algae.

Preventing algae from returning

Maintain a stable chlorine level, brush walls regularly, keep the water well-balanced, and perform preventive maintenance with products like the BioGuard range. Activate the Analyzer's reminders so you never let your chlorine drop.

Recommended products

• Chlorine and shock treatment
• Algaecides
• Clarifiers and solutions for cloudy water
• BioGuard products
• Water analysis

Frequently asked questions

My water is green but my chlorine level is high—why?
Often a pH or stabilizer problem that renders chlorine ineffective, or resistant algae. Test your water to pinpoint the true cause.

Can I swim during treatment?
Wait until safe levels are restored after a shock treatment—refer to the product label.

Do I need to empty the pool?
Almost never. In the vast majority of cases, green water can be restored without draining.

➞ Analyze my water and get my recipe