It’s the first warm weekend of spring. You pull back the cover, ready for a swim, and the water looks like a pond.
It happens to more Sydney pools than you’d think, and you can fix it. Here’s what’s going on, what you can do yourself, and when to call us.
Cloudy comes first
Most green pools start out cloudy. The water looks dull and milky, and the floor starts to fade from view.
That’s your warning. Something’s off, and algae is about to take advantage of it.
Why is my pool cloudy?
Low chlorine. There’s not enough sanitiser to keep the water clean.
High pH or alkalinity. Chlorine stops working properly.
A dirty or blocked filter. The water isn’t being cleaned.
The pump isn’t running long enough, or at all.
Heavy rain. It waters down your chemicals and washes in dirt and leaves.
Why is my pool green?
Green means algae. It grows fast in still water with low chlorine, and warm spring days after a quiet winter give it everything it needs. It often starts with a pump that stopped working, or one that was switched off over winter to save power.
Salt water pools go green too. A salt cell that’s scaled up, worn out or turned down for winter stops making enough chlorine.
How to fix a cloudy or green pool
- If the water is cloudy or light green, you can often sort it yourself.
- Test the water. Use a test kit or take a sample to your local pool shop. Check chlorine, pH and alkalinity before you add anything.
- Get the pH right. Aim for 7.2 to 7.6, where chlorine works best.
- Clean the filter. Backwash a sand filter or hose out your cartridge.
- Shock the pool. Add a big dose of chlorine and follow the directions on the pack. Do it in the evening so the sun doesn’t burn it off.
- Brush everything. Walls, floor, steps and corners. Algae hides where the water doesn’t move.
- Run the pump around the clock until the water clears.
- If it’s still cloudy, use a clarifier or floc. Floc sinks the cloudiness to the floor overnight, then you vacuum it out to waste.
Light green usually clears in a few days. Cloudy water can take a bit longer.
A word on safety. Never mix pool chemicals together. Always add chemicals to water. Keep everyone out until you can clearly see the floor. If you can’t see the bottom, you can’t see someone in trouble.
When to call in help
Some pools need more than a weekend of work. Give us a call if…
- The water is dark green or black.
- You’ve shocked it twice and it still won’t clear.
- The pump won’t start, hums, leaks or trips the power.
- Black spots on the walls won’t brush off.
- You’d rather have your weekend back.
Our green pool recovery service gets you swimming again fast. If the pump is the problem, we’ll fix that too.
Stop it happening again
Most green pools come down to one thing. Nobody was keeping an eye on it.
Run the pump every day. Test the water every week. Keep the filter clean. Check the pool after a big storm.
Or leave it to us. Same technician, same day, every week. We catch cloudy water before it turns green, so every time you lift the cover, the pool is ready to jump in.
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