You're swimming over it every day. Kill it in 24 hours, keep swimming this week.
Black spot spread under the cover all winter. Now the pool is open, you can see exactly how far. One jar kills it in under 24 hours, no draining, no scrubbing. Get 4 jars for $179.97 with the 4th FREE, plus free shipping.
✓ 30-day money back · Australian made · Fast dispatch
Water TechniX Black Spot Remover 1kg
Choose your pack
Black spot algae etches into pool surfaces permanently if left untreated. Resurfacing costs $3,000 to $8,000. Treating it now is the only cheap option.
★★★★★ 1,240+ Australians
killed black spot before it took over their pool
- Kills black spots fast: Visible results in under 24 hours. Spots turn grey, then disappear.
- Surface safe: Concrete, pebblecrete, quartzon, fibreglass, vinyl and tile. Use skimmer method for softer surfaces.
- Concentrated power: 900g/kg trichloroisocyanuric acid. Professional-grade slow release formula.
- Prevents regrowth: Kills the root to stop it coming back season after season.
- Dosage: 1kg treats up to 25,000L. For heavy infestations, a second application is recommended.
Already swimming? You can treat it while you swim. You'll be back in the water within 48 hours, and the black spot stops spreading immediately.
Why this works when others don't
Quick answers
Most pool owners see black spots turning grey within 24 hours. For heavy infestations a second application a week later is recommended. With four jars you have enough for follow-up treatments.
Yes. For fibreglass, vinyl, quartzon and tiled pools, add it via the skimmer basket rather than direct application to avoid bleaching. Concrete and pebblecrete can be spot-treated directly.
Wait at least 48 hours and confirm chlorine is back to 2 to 4 ppm and pH is 7.2 to 7.6 before swimming.
Yes. You don't need to drain or wait for the off-season. Apply the treatment, stay out of the water for 48 hours, and you're back to swimming. The longer you put it off, the deeper the algae roots grow and the harder it gets to kill.
The Black Spot Nightmare
You've scrubbed, shocked and tried every DIY trick. Yet those stubborn, deeply rooted black spots keep coming back. After a full winter under the cover, they're spreading further every time you swim.
Endless Scrubbing
You scrub every weekend and it never lasts. The spots are back within a month.
Wasted Money
Regular algaecides simply don't work on black spot algae. It has a protective waxy layer.
Permanent Damage
Left untreated, black spot algae etches into and ruins pool surfaces permanently.
Every Swim Spreads It
You're in the water every week. Every splash and brush against the wall spreads the spores further.
In-Season Warning
Every Swim Adds Another Layer. Treat It This Week.
The pool is open, the kids are in and the sun is out. Every week those black spots sit there, the warm water, the chlorine and the foot traffic help them spread. You can still treat them while you swim. Four jars handle your pool and a follow-up round, and get you back to clear water within a week.
Serious Chemistry. Here's How to Use It Safely.
Trichloroisocyanuric acid is a professional-grade active ingredient. That's what makes it work when nothing else does. Follow these steps and you'll have no issues.
Wait 48 hours before swimming
The formula super-chlorinates the water to kill algae at the root. Before getting back in, check that chlorine is between 2 and 4 ppm and pH sits between 7.2 and 7.6.
Fibreglass, vinyl, quartzon or tiled pool? Apply via the skimmer basket
Direct application on softer pool surfaces can cause localised bleaching. Add the granules to your skimmer basket instead. The same high-concentration chlorine circulates and kills the algae without touching the surface directly.
Concrete or pebblecrete pool? Spot treat directly on the affected areas
Hard surfaces handle direct contact without bleaching. Apply granules directly onto the black spot patches. Brush first to break the algae's waxy outer layer, then apply.
How Black Spot Remover Eliminates Algae
Water TechniX Black Spot Remover uses a slow-dissolving, concentrated formula. It gradually releases high-strength granular chlorine (active: trichloroisocyanuric acid 900g/kg) over 24 hours, breaking down the algae's tough outer layer and penetrating its root system to kill it completely.
Concentrated Power
High-strength formula targets algae directly where other products can't reach.
Slow Release Action
Gradually releases sanitiser over 24 hours for prolonged, sustained algae attack.
Penetrates and Destroys
Breaks down the protective waxy layers and kills algae at its core and roots.
Prevents Regrowth
Eliminates the source so it won't come back harder next season.
Simple Steps to a Spotless Pool
Treat it while the pool is in use. You'll be back to swimming within the week.
Application Instructions
Brush Affected Areas
Vigorously brush the black spots with a stainless steel brush (for concrete or pebble) or a nylon brush (for vinyl or fibreglass) to break the algae's protective waxy layer.
Apply the Product
For concrete and pebblecrete pools:
Apply the product directly onto the affected areas (spot treat).
For vinyl, fibreglass, quartzon and tiled pools:
Apply the product directly into the skimmer basket. Direct application on softer surfaces can cause bleaching.
Circulate, Then Brush and Vacuum
Run your pool pump for at least 24 hours. After 24 to 48 hours, brush away dead algae (it typically turns grey or white) and vacuum the waste to waste or filter.
Important Safety Note
Do not swim for at least 48 hours after treatment. This product super-chlorinates the water, which may cause skin and eye irritation.
Before re-entering the pool, ensure your water is balanced:
- ✓ Chlorine: 2 to 4 ppm (summer) | 2 to 3 ppm (winter)
- ✓ pH: 7.2 to 7.6
Always read and follow the full product label instructions and safety precautions.
Oxi Shock 500g: The Perfect Follow-Up
After the Black Spot Remover does the heavy lifting, use Oxi Shock to clean up the mess. It oxidises the dead algae and organic waste, softens the water and removes that itchy skin feeling.
Dosage: 1 x 500g tub treats up to 40,000L.
- Removes dead algae: Acts as the cleanup step for your pool after treatment.
- Eliminates itch: Removes chloramines that cause itchy skin and red eyes.
- Lightning fast: Swim-ready in just 15 minutes.
What Our Customers Are Saying
Works on every pool surface
More from our customers
"Honestly, I was about to give up. My pebblecrete pool was covered in black spots that just wouldn't budge. Gave this stuff a go and wow, it actually worked! The spots are completely gone."
"What a lifesaver! I was so over spending my weekends scrubbing. This stuff saved me so much time. My pool seriously has never looked this good. Highly recommend it!"
"Was getting so frustrated with stubborn black spots. I just followed the instructions and within a week the patches were gone. Pool is looking crystal clear again."
Stop Swimming Past It.
Kill It This Week.
Four jars for $179.97. That's $44.99 each. Enough to treat your pool and follow up on any stubborn patches. Free shipping included. Back in the water within 48 hours of each treatment.