Waterbody type
Plastic-lined irrigation dam
| Primary issue
Extreme legacy nutrient loading
| Treatment method
Ultrasonics + PBE
| Measured severity
Up to 230× above recommended levels
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The challenge
A dam under constant algae pressureThis South Australian irrigation dam serviced a hothouse vegetable and herb operation. While normal roof runoff entered the dam, the deeper issue was years of pump backflush and hydroponic waste being discharged directly into the system. Repeated use of copper sulphate and other algaecides contributed to nutrient lock-up in the water and sludge, creating a high-risk environment where algae could rapidly re-establish. Testing showed several nutrient levels at up to 230 times above recommended levels, meaning algae had an unusually strong and ongoing food source. |  Precise deployment matters
Drone-assisted placement supports accurate positioning of PBE across larger treatment areas, helping establish the biological system where it can be most effective.
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A two-pronged strategy designed to treat both symptoms and source conditions
Next-generation ultrasonics
Ultrasonics were used to disrupt algae activity and suppress bloom formation, reducing the dominance of problematic organisms in the waterbody.
| PBE — Prebiotic Bacteria Enhancer
PBE helps convert locked-up nutrients into plant-available forms, allowing crops to absorb them instead of leaving them behind to drive future blooms.
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Six weeks in, the combined system was already showing measurable impact
The combined system was suppressing active algae while the nutrient trend began shifting. The chart below shows the broader nutrient movement that supports the case for PBE as a catalyst for longer-term recovery.
Key algae and nutrient graphs at readable size
 Overall algae trend showing the strong early decline from an elevated baseline.
|  Collapse of the most problematic bloom-formers in the early treatment window.
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 Species-level cyanobacterial response, reinforcing the collapse result in more detail.
|  Green-algae trend showing how the system may shift toward more balanced species over time.
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 Species-level visibility for the green algae response, adding context to overall counts.
| Multi-line nutrient tracking that supports the longer-term case for nutrient drawdown.
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Why rising counts later may not mean the system is failing
Higher total algae counts later on do not automatically indicate a worsening bloom. In a healthier system, non-nuisance green algae can increase as the waterbody rebalances and the original problem organisms lose dominance.
That means interpretation matters: total counts alone are less important than the species shift, the collapse of cyanobacteria, and the longer-term nutrient trend.
This is why combining ultrasonics with PBE matters — one suppresses harmful bloom activity while the other helps address the nutrient reservoir feeding future outbreaks.
Restoring balance requires more than algae knockdown alone
This case study shows why waterbody recovery is strongest when suppression technology and biological nutrient management work together. The early results support a clear direction of travel: reduced algae pressure, improving nutrient dynamics, and a more stable irrigation asset over time.
