Tips For Pool Owners During La Nina Weather
Don’t let La Niña ruin your summer of poolside fun! Heavy rainfall means leaves, dirt and algae spores get delivered into your pool. Phosphates get deposited into the water and chlorine, salt and minerals are diluted. Combined with sunlight, these conditions are perfect for algae to grow and turn your healthy pool, into a green pool. It also affects the water’s pH, calcium hardness, total dissolved solids, alkalinity and other chemical levels.
What is La Nina?
The Bureau of Meteorology has warned to expect a La Niña weather pattern this summer, which is set to bring mass wet weather across the parts of New Zealand – with backyard pool owners warned to prepare for a whirlpool of challenges.
What are the effects of La Nina?
Typically during La Niña seasons, there is above average rainfall with extra rain, some storms and possibly even flooding expected.
Poolwerx Founder and CEO John O’Brien says the effects of this excess rain are pretty significant on your pool and could have a huge impact on backyard summer fun.
“It is pivotal for pool owners to prepare in advance, and work with their local Poolwerx team to manage these effects during and after the season, to ensure they still have a healthy pool to create backyard family memories in. The solution is simple – prepare in advance and take the necessary steps to avoid greater cost and energy to remedy the situation after summer.”
La Nina & Your Pool
The effects of this excess rain can have a significant impact on your pool’s health if you don’t look after it properly.
Along with the usual culprits that accompany heavy rain, such as debris, garden runoffs, overflow and contaminates, La Niña brings additional long-term consequences – the dilution of pool chemicals, green pools, and increased risk of mosquito-borne viruses.
Below is our easy guide for New Zealanders to help you maintain a healthy pool during stormy weather
Tips for La Nina Pool Care
Tip #1: Prepare Your Pool For Rain
Before rain hits, it’s important to balance the pool properly. Consider adding some Focus Algicide to help fight off many of the organic contaminants the rainwater introduces, making it easier to clean the pool after the rain dissipates

Tip #2: Clean The Pool After Rain
Once the rain has passed, you can begin to clean the pool – but you’ll want to act fast, as if the pool isn’t cleaned and the chemical imbalance isn’t corrected quickly, this can damage pool equipment leading to expensive repairs.
Empty the skimmer and pump baskets and remove large debris and leaves from the water. They will influence the water chemistry of the pool and potentially stain the pool’s surface.
Tip #3: Regular Pool Water Testing
Storms and heavy rain can greatly affect the pH, water chemistry and chlorine levels of your pool. As a result, it’s recommended that you regular test your pool water after a storm or heavy rain in order to prevent an algae outbreak, brown pool or costly clean up bill.
Test & balance the pool water
Poolwerx provides water testing in-store. Take a sample of pool water to your local Poolwerx for a water test where our experts will analyse the results and recommend the best products for your pool.
Handy tip: Always take a water sample at elbow depth to get an accurate water chemistry reading – especially after heavy rain.

Tip #4: Add a Floccing Agent
Heavy rainfall can lead to water runoff into your pool containing dirt, soil and mud. If your pool is looking brown, add Focus Quick Floc
This is a fast-acting agent and perfect to use after rainstorms as it binds dirt and mud particles together to the bottom of the pool floor where they can be vacuumed.
Fixing a Brown Pool
Heavy rainfall can lead to water runoff into your pool containing dirt, soil and mud. If your pool is looking brown, add Focus Quick Floc.
This is a fast-acting agent and perfect to use after rainstorms as it binds dirt and mud particles together to the bottom of the pool floor where they can be vacuumed.

Tip #5: Use an Algaecide
During a rainstorm, leaves, dirt and algae spores get delivered into pool water. Phosphates get deposited into the water and chlorine, salt and minerals get diluted. Combined with sunlight, these conditions are perfect for algae to grow and affect the health of a pool, leading to a green pool. In addition, if rainwater runs off the property’s roof or deck, it can also introduce foreign contaminants, alter the water’s pH, calcium hardness, total dissolved solids, alkalinity and other chemical levels.
Stop Algae Growing
Leaves, dirt and algae spores delivered into the pool water decompose, causing phosphates to be deposited into the water, which can result in a green pool once the sun comes out – and fast! Ensure you maintain correct chlorine levels as this will not only help keep your pool clean & healthy but will also help to prevent additional water usage and avoid you having to fix issues such as a ‘green pool’. If your pool has turned green after a storm, try using an algaecide, such as the Focus Algicide Concentrate to effectively kill the algae in the pool.

Tip #6: Use a Shock Treatment
Your pool water may appear cloudy as your chlorine, salt or minerals have been diluted. We recommend Focus Shock and Clear to help get your pool water sparkling again.
Prevent Cloudy Pools
Rain can dilute the chlorine, salt or minerals to where you can’t see the pool floor, but the water is a non-green colour. A quality pool clarifier or shock treatment such as Focus Shock & Clear will work to catch and group the tiny particles. This makes them easier for the filter to collect
and remove.

Tip #7: Schedule A Pool Service
After a storm it’s important to service your pool and check your equipment. By arranging for Poolwerx to service and maintain your pool, you can be assured it will be back in top condition in no time.
So there you have it, our top tips to keep your pool on track this summer! Don’t forget our local qualified technicians can help with all your pool care needs.