Theoretical Formulation of Organic-Fertilizer Feedstocks from Filter Aid, Seaweed Residue, and Cattle Manure : Formulasi Teoretis Bahan Baku Pupuk Organik dari Filter Aid, Residu Rumput Laut, dan Kotoran Sapi

Dipa Aditya (Program Studi Agribisnis, Fakultas Pertanian, Universitas Mayjen Sungkono, Mojokerto, Indonesia.)
Dedy Sekarmaji (Program Studi Agribisnis, Fakultas Pertanian, Universitas Mayjen Sungkono, Mojokerto, Indonesia.)
Desy Ratnaningrum (Program Studi Kimia Murni, Universitas Airlangga, Surabaya, Indonesia.)

Jurnal Ilmiah Manajemen Agribisnis
Vol. 14 No. 2 (2026): Vol. 14 No. 2 (Juli - Desember 2026) Jurnal Ilmiah Manajemen Agribisnis

Agro-industrial and livestock residues are potential organic-fertilizer feedstocks, but their composition must be screened before experimental composting. This study developed a theoretical formulation of filter aid, seaweed-processing residue, and cattle manure using a linear mixture model and mass-balance calculations based on existing laboratory characterization data. Under a screening scenario targeting an initial C/N ratio of 24 and an equal share of seaweed residue and cattle manure, the candidate proportion was 0.278:0.361:0.361 (approximately 1:1.30:1.30). The mixture was projected to contain 17.19% organic carbon, 0.85% nitrogen, a C/N ratio of 24.00, 281.71 ppm available Fe, 14,010.74 ppm total Fe, and an estimated pH of 5.76. These values fall within the screening limits used for the available parameters, but they do not demonstrate compliance of a finished organic-fertilizer product because P, K, moisture, heavy metals, maturity, and other required parameters were not evaluated. The study therefore provides a proof-of-concept formulation and identifies total Fe and raw-material variability as critical issues for subsequent composting, laboratory validation, and plant testing.