The Tennis Ball trick - for sunscreen this time!
The Tennis Ball Trick: Does It Really Remove Pool Oils and Sunscreen?
A simple solution for keeping your pool surface clean between services
If you've spent any time in pool owner Facebook groups or forums, you've probably heard about the tennis ball trick - tossing a few tennis balls into your pool to absorb body oils, sunscreen, and other greasy residues that float on the water's surface. But does it actually work, or is it just another pool maintenance myth?
How the Tennis Ball Trick Works
The concept is surprisingly simple. Tennis balls are made from felt-like material that's naturally hydrophobic (water-repelling) but lipophilic (oil-attracting). When a tennis ball floats on your pool surface, the fibres absorb oils, sunscreen, lotions, and other oily contaminants that would otherwise create that unpleasant film you sometimes see on the water.
As the ball bobs around the pool, blown by wind and disturbed by swimmers, it continuously collects these oils from the surface. It's essentially a passive skimming system that works 24/7 without any effort on your part.
How Effective Is It Really?
The tennis ball trick is genuinely effective for light to moderate oil and sunscreen buildup. It works best as a preventative measure rather than a cure for existing problems. Here's what you can expect:
- Daily accumulation of body oils from regular swimming
- Light sunscreen residue from a few swimmers
- Natural skin oils and cosmetics
- Hair products and light lotions
- Heavy sunscreen loads (like after a pool party)
- Existing scum lines on tiles
- Oils that have already emulsified into the water
- Contamination that's migrated below the surface
Think of tennis balls as your first line of defence, not your complete solution. They're brilliant at keeping a relatively clean pool clean, but they won't rescue a pool that's already developed significant surface contamination.
How Often Should You Replace the Balls?
Tennis balls become saturated with oils over time, losing their effectiveness. You'll need to replace them based on pool usage:
- Light use (family pool, occasional swimmers): Replace every 3-4 weeks
- Moderate use (regular swimming, frequent entertaining): Replace every 2-3 weeks
- Heavy use (daily swimming, pool parties, high traffic): Replace weekly
A saturated tennis ball will sit lower in the water and feel heavy and greasy when you squeeze it. Once you notice this, it's time for fresh ones.
Where to Place Tennis Balls in Your Pool
For maximum effectiveness:
- Use 2-3 balls for an average residential pool (around 40,000-50,000 litres)
- Place one in the skimmer box - this captures oils before they spread across the surface
- Float 1-2 balls freely on the surface - let them drift with wind and water movement to cover different areas
- Add an extra ball near steps and ladders where people enter and exit frequently
The beauty of this method is that you don't need precision - the balls will naturally move around and find the oils.
Tennis Meets Swimming: A Fun Connection
Here's an interesting bit of trivia: both tennis and swimming were sports favoured by royalty and the wealthy in the 19th century. While lawn tennis was being perfected at England's All England Club (home of Wimbledon) in the 1870s, the first modern swimming pools were being built at exclusive clubs and estates. Both sports eventually became accessible to everyday Australians, and now those tennis balls have found a second life helping maintain the very pools where we cool off after a game!
When the Tennis Ball Trick Isn't Enough: The Proper Solution
If you're dealing with significant oil contamination, visible surface scum, or the tennis balls alone aren't keeping up, it's time for a more comprehensive approach using quality pool chemicals.
For Surface Oil and Scum: Lo-Chlor Surface & Tile Cleaner
When you've got stubborn oils floating on the surface or that tell-tale greasy film, Lo-Chlor Surface & Tile Cleaner is your go-to solution. This enzyme-based cleaner specifically targets oils, sunscreen, and cosmetic residues without affecting your pool's water chemistry.
How to use it:
- Add 500ml per 50,000 litres directly to the pool water
- Run your filtration system for at least 8 hours
- The enzymes will break down oils both on the surface and in the water
- Safe to swim immediately after application
- Use monthly during summer or after heavy pool usage
This product works brilliantly in combination with tennis balls - the cleaner removes existing contamination while the balls prevent new buildup.
For Cleaning Scum Lines: Lo-Chlor Tile & Vinyl Cleaner
That unsightly scum line at the waterline doesn't just look bad - it's a breeding ground for bacteria and can stain your tiles or vinyl liner over time. Lo-Chlor Tile & Vinyl Cleaner is specifically formulated to remove this buildup without damaging your pool surfaces.
Application method:
- Use undiluted for heavy buildup, or dilute 1:1 with water for regular maintenance
- Apply with a sponge or soft brush at the waterline
- Scrub gently - let the chemistry do the work
- Rinse into the pool (it won't affect water chemistry)
- For stubborn stains, allow to sit for 2-3 minutes before scrubbing
Pro tip: Clean your scum line every 2-4 weeks during summer to prevent heavy buildup. It's much easier to maintain a clean line than to remove months of accumulated oils.
The Complete Prevention System
For Perth pool owners looking to stay ahead of oil and sunscreen contamination, here's your complete strategy:
- Prevention: Keep 2-3 tennis balls floating (replace regularly)
- Water treatment: Use Lo-Chlor Surface & Tile Cleaner monthly during swimming season
- Physical cleaning: Clean waterline with Lo-Chlor Tile & Vinyl Cleaner every 2-4 weeks
- After parties: Always use Surface & Tile Cleaner after heavy pool usage
Additional Tips and Tricks
Encourage family and guests to rinse off before swimming. A quick 30-second shower removes the majority of sunscreen, oils, and cosmetics before they enter your pool. It's the single most effective prevention method.
Between chemical treatments, keep a dedicated microfibre cloth near your pool. A quick wipe around the waterline during your regular pool check removes fresh oils before they set into a scum line.
A quick skim of the surface with your pool net every couple of days removes floating debris and breaks up oil patches, making your tennis balls and chemicals more effective.
Placing a tennis ball in your skimmer box is particularly effective because it captures oils at the point where water is being drawn into your filtration system. Change this ball more frequently than the floating ones as it will saturate faster.
The Bottom Line
The tennis ball trick is a legitimate, cost-effective way to reduce surface oils and sunscreen in your pool. At around $10 for a pack of balls that'll last a month or two, it's one of the cheapest maintenance tricks available. However, it works best as part of a complete maintenance routine, not as a standalone solution.
For Poolwise Padbury customers in Perth's northern suburbs, we stock the complete range of Lo-Chlor products and can advise on the best combination for your specific pool conditions. Whether you're dealing with regular family use or hosting frequent pool parties, we'll help you maintain that crystal-clear water with minimal effort.
And yes, we'll even throw in some tennis balls with your next Lo-Chlor purchase!
Have questions about pool maintenance or need help selecting the right products?
Visit us at Poolwise Padbury or give us a call. We're your local experts for keeping Perth pools pristine.
