Sustainable Sludge Reduction with SchlixX Plus
Polishing Pond – Lahntal Göttingen Wastewater Treatment Plant
“After the treatment, only a thin, even layer of sediment remained on the bottom. There’s slightly more in the deeper areas, but overall, we’re extremely satisfied with the result.”
Project highlights
Impressive impact: approx. 600 m³ of organic sludge removed
Natural balance preserved: no mechanical excavation required
Climate-friendly: reduced potential methane formation and improved oxygen balance
The starting point
A Pond at the Limit
Nestled in the northern Hessian landscape near Cölbe lies the Lahntal Göttingen wastewater treatment plant. Over the years, its polishing pond had reached a critical point: increasing layers of organic sludge and nutrient inputs from treated wastewater fueled excessive algae growth. The ecological balance shifted, water quality declined and the pond steadily lost depth.
The solution
SchlixX Plus – Oxygen and Aquatic Microorganisms as the Key to Regeneration
In collaboration with a German water technology partner, OASE deployed SchlixX Plus — the innovative product for biological sludge reduction.
Its mineral-based active complex gradually releases oxygen over several weeks, allowing aerobic microorganisms to break down organic sludge with exceptional efficiency — all without disturbing the pond structure. SchlixX Plus also contains specific aquatic bacteria that further accelerate the decomposition of organic material.
The successes
Measurable Results, Visible Transformation
Within just a few months, clear effects were observed:
- 600 m³ of sludge were biologically degraded — without dredging or pumping
- The organic content in the sediment dropped by 8.4%
- The gravel layer at the bottom became visible again.
Stable Water Values, Sustainable Impact
All measurements confirmed stable water quality and a strengthened ecological balance. SchlixX Plus worked gently yet highly effectively — a perfect blend of environmental compatibility and technical precision.
Natural Regeneration Instead of Intervention
The Lahntal/Göttingen project demonstrates impressively that even heavy sludge accumulation can be reduced naturally with SchlixX Plus — without costly, invasive mechanical methods.
The polishing pond was treated gently, regained volume and the water became noticeably clearer.
Recommendation for Long-Term Clarity
Nutrient inputs from the treatment plant will continue in the future, so regular, seasonal use of SchlixX Plus is recommended to maintain a stable ecosystem. This keeps water quality high and ensures the pond remains a vital, efficient component of the wastewater treatment process.
OASE – Your Partner for Healthy, Stable Water Bodies
Would you like to improve the ecological condition of your waterbody, counteract sludge accumulation and protect nature sustainably?
Contact us or your local OASE partner. Together, we develop solutions that restore balance, strengthen ecosystems and deliver visible, lasting results.
Project fact sheet
| Project name | Wastewater Treatment Plant Lahntal |
| Country | Germany |
| City/region/area | Lahntal |
| Waterbody type | Polishing pond |
| Usage and size | Wastewater treatment plant; pond size: 1 ha |
| Challenge | Excessive sludge accumulation and algae growth |
| Product used | SchlixX Plus |
| Application Period & Method | In July 2024, approx. 1,050 kg of SchlixX Plus was applied using an amphibious vehicle |
| Result of the application | Approval to open the entire lake by the local health authority on 2 August 2022
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