How To Remove Algae From Pool Without Chemicals

Understanding Algae in Your Pool

If you own a pool in New Zealand, you’ll know that algae can be a common and frustrating problem, particularly in warmer months. Algae thrive in stagnant or unbalanced water, quickly turning a clear pool into a green, cloudy mess. While many pool owners turn to chemicals like chlorine and algaecides to treat it, there are plenty of effective natural methods to remove and prevent algae.

In this guide, I’ll share practical steps to get rid of algae without using chemicals—great if you prefer an eco-friendly approach or have sensitivities to harsh products.

Step 1: Remove Debris and Scrub the Pool

Before tackling the algae itself, it’s crucial to remove any leaves, dirt, or organic matter that may be floating in your pool. Organic debris provides nutrients that algae feed on, making it harder to get the water clear again.

Skim the surface and vacuum the bottom using a pool net and a manual or robotic vacuum.
Brush the walls and floor of your pool thoroughly. Algae often cling to surfaces, and scrubbing will loosen it. A stiff-bristled pool brush is best for concrete or plaster pools, while a softer brush works well on vinyl-lined pools.

Step 2: Improve Filtration and Circulation

One of the main causes of algae growth is poor water circulation. If your pool pump or filter isn’t running efficiently, algae can quickly take hold.

Run your pool pump for at least 8-12 hours per day to help filter out algae spores and debris.
Check and clean your pool filter to ensure it’s working correctly. If you have a sand filter, backwash it. For cartridge filters, rinse them properly and replace if necessary.

New Zealand retailers like Trade Depot and Pool & Spa Warehouse NZ offer pool pumps and filters if you need replacements or upgrades.

Step 3: Use Natural Algae-Fighting Methods

1. Increase the Oxygen and Circulation with a Water Feature

A stagnant pool is an easy place for algae to grow. Adding a water feature such as a fountain or aerator increases circulation and oxygen in the water, making it harder for algae to thrive.

2. Use a Pool Vacuum to Remove Settled Algae

After scrubbing, much of the algae will be floating around in the water. A manual pool vacuum (set to “waste” mode if available) will help remove it before it settles again.

3. Use Baking Soda to Loosen Algae

Baking soda (sodium bicarbonate) is an excellent natural treatment for pool algae. Simply sprinkle baking soda onto affected areas and scrub with your brush—it helps loosen algae so it can be vacuumed away. Stores like The Warehouse and Mitre 10 stock baking soda at affordable prices.

4. Try a UV Pool Sanitiser

Ultraviolet (UV) pool systems are an effective alternative to chemicals. They use UV light to kill bacteria and algae spores before they start multiplying. While the initial cost may be higher, it’s a natural and long-term solution. Check out Aqua Synergy Group for UV systems in New Zealand.

Step 4: Balance Your Water Naturally

Keeping your pool water balanced is key to preventing algae growth in the first place. If your pool’s pH and alkalinity are out of balance, it creates an ideal environment for algae.

Check and adjust pH levels to 7.2 – 7.6 using natural alternatives like vinegar.
Maintain alkalinity between 80-120 ppm using baking soda if needed.
Keep phosphate levels low by regularly removing organic debris, as phosphates act as food for algae.

You can find pool water testing kits at retailers such as Bunnings NZ or online at Pool & Spa Warehouse.

Step 5: Prevent Algae from Coming Back

Once your pool is clear, prevention is key. Here’s how to keep algae away naturally:

Use a pool cover when your pool isn’t in use to block sunlight (which algae need to grow).
Maintain regular cleaning by brushing walls and vacuuming at least once a week.
Encourage circulation with a floating solar-powered skimmer or additional water features.
Keep your filter clean—a clogged filter won’t catch algae spores effectively.

Enjoy a Naturally Clean Pool

Using these chemical-free methods, you can keep your pool algae-free while being kinder to the environment. With a bit of consistency in cleaning and maintaining water balance, you’ll enjoy clear, fresh water all summer long.

If you’re looking for eco-friendly pool products, check out local suppliers like Eco Pools NZ for additional advice or solutions.

Have you successfully removed algae naturally from your pool? Share your experiences in the comments below!

Pool Owners New Zealand