Assessing the Feasibility of Septage-Derived Struvite as a Nutrient Solution Alternative through Hydroponic Kangkong (Ipomoea aquatica L.) Growth Trials

Proponent/s Name/s (Last Name, First Name, Middle Initial)

• Carlos Iñigo G. Zamora, De La Salle University, ManilaFollow
• Amber Kelly B. Sarmiento, De La Salle University, ManilaFollow
• Venice A. Salvador, De La Salle University, ManilaFollow
• John Gabriel M. Lee, De La Salle University, ManilaFollow

Document Types

Paper Presentation

Research Theme (for Paper Presentation and Poster Presentation submissions only)

Sustainability, Environment, and Energy (SEE)

School Name

De La Salle University, Manila

Track or Strand

Science, Technology, Engineering, and Mathematics (STEM)

Research Advisor (Last Name, First Name, Middle Initial)

Pausta, Carla Mae, J. / Belo, Lawrence, P.

Start Date

25-6-2026 10:30 AM

End Date

25-6-2026 12:00 PM

Zoom Link/ Room Assignment

Online- https://zoom.us/j/92594857524 Meeting ID: 925 9485 7524 | Passcode: research

Abstract/Executive Summary

Climate change, wastewater management, and the increasing dependence on non-renewable phosphate fertilizers have necessitated sustainable agricultural alternatives. Therefore, this study aimed to compare the growth performance of Ipomoea aquatica L. grown under a commercial hydroponic nutrient solution and a struvite-based solution supplemented with potassium nitrate (KNO3), while also evaluating nutrient solution stability through pH and electrical conductivity (EC). A four-week hydroponic growth trial following 22 days of preliminary cultivation was conducted using two nutrient setups with nine recorded replicates each. Plant height, mean leaf area, number of leaves, stem diameter, fresh weight, dry weight, root length, pH, and EC were recorded throughout the trial. Weekly growth parameters were analyzed using repeated measures ANOVA, while Welch’s one-way ANOVA was used for post-harvest biomass parameters. Results showed significant effects of Week across all growth parameters, indicating that both nutrient solutions were capable of supporting plant growth. Significant Setup × Week interactions were observed for mean leaf area, number of leaves, and stem diameter, suggesting differences in nutrient availability and growth progression over time. Although the commercial nutrient solution generally promoted faster vegetative growth and greater biomass accumulation, the struvite-based solution still supported continuous and stable plant development. These findings suggest that septage-derived struvite has potential as a sustainable alternative nutrient source for hydroponic cultivation systems, particularly when supplemented to address nutrient limitations and evaluated under longer growth periods.

Keywords

hydroponics; struvite; kangkong; deep water culture; nutrient recovery

Initial Consent for Publication

yes

Statement of Originality

yes