## 5 Conclusions  
The evaluation of the PF200 water treatment system reveals both potential advantages and significant challenges. The system's low energy consumption and minimal maintenance demands are attractive, while the technical and operational issues limit its current applicability. Over the study period, the average turbidity of the treated water was 0.54 NTU, resulting in only 47.1% compliance with the US EPA standard of <0.3 NTU. Additionally, the process generated a waste stream averaging over 10% of the raw water volume, reducing overall efficiency. Future work should emphasize improved coagulant dosing strategies, enhanced design to minimize waste, and comprehensive testing against a broader range of contaminants, including bacterial and viral contaminants, nutrients, and emerging contaminants like microplastics and PFAS.  
Robust performance validation and life cycle assessments are required to confirm PF200's viability as a portable, small-scale water treatment alternative. The tested water treatment system shows promise due to its low maintenance requirements and energy efficiency, qualities particularly relevant in regions facing workforce shortages and infrastructure challenges [57; 58]. However, both the poor performance and the significant wastewater production of the pilot pose significant obstacles to its widespread adoption. Contingent on meeting the quality standards and other legal requirements, clear advantages in the field of O&M might lead to positioning PF200 as an attractive alternative for the users in need of a robust, portable, small-scale water treatment system.  
The following supporting information can be downloaded at [[https://www.mdpi.com/article/10.3390/app15126668/s1](https://www.mdpi.com/article/10.3390/app15126668/s1)]([https://www.mdpi.com/article/10.3390/app15126668/s1](https://www.mdpi.com/article/10.3390/app15126668/s1)), S1--Manual: construction manual for the tested PF200; S2--Moroceli: performance data of the AguaClara plant in Moroceli, Honduras.  
**Author Contributions**: Conceptualization, M.S. and R.E.R.; methodology, M.S. and R.E.R.; software, M.S.; validation, M.S., P.K. and R.E.R.; formal analysis, M.S. and P.K.; investigation, M.S.; resources, R.E.R.; data curation, M.S. and P.K.; writing--original draft preparation, M.S. and P.K.; writing--review and editing, M.S., P.K. and R.E.R.; visualization, M.S.; supervision, R.E.R.; project administration, R.E.R.; funding acquisition, R.E.R. All authors have read and agreed to the published version of the manuscript.  
This research was funded by the United States National Science Foundation, Grant #s 1919084 and 1704472.  
**Institutional Review Board Statement**: Not applicable.  
**Informed Consent Statement**: Not applicable.  
**Data Availability Statement**: Data available online; information about the technology released to the public domain and available online at [[https://github.com/aguaclara](https://github.com/aguaclara)]([https://github.com/aguaclara](https://github.com/aguaclara)) (accessed on 10 June 2025).  
**Acknowledgments**: The authors would like to acknowledge [PERSON], founder of AguaClara, for advising on the design and construction of the PF200 setup, as well as [PERSON] and the rest of the Cornell University Water Filtration Plant personnel, for their ongoing support and for hosting the experiments.  
**Conflicts of Interest**: The authors declare no conflicts of interest.