Penelitian ini bertujuan untuk mengetahui pengaruh dosis pupuk NPK dan ZA terhadap pertumbuhan Gracilaria changii. Penelitian ini dilaksanakan pada bulan Februari hingga Maret 2025 selama 35 hari, di Desa Totoli, Kecamatan Banggae, Kabupaten Majene, Provinsi Sulawesi Barat. Penelitian ini mengambil metode Rancangan Acak Lengkap (RAL), 4 perlakuan dengan 3 kali ulangan. Analisis data dilakukan menggunakan analisis data statistik di Excel. Hasil penelitian ini menunjukkan bahwa dosis pupuk NPK dan ZA yang dilakukan didalam laboratorium kurang efektif terhadap laju pertumbuhan Gracilaria changii. Laju pertumbuhan mutlak yang diperoleh dari perlakuan A (NPK 1g/l : TSP 1g/l) yaitu -173,6 g, perlakuan B (NPK 0,5g/l : ZA 1g/l) -156 g, perlakuan C (NPK 1g/l : ZA 1g/l) -100 g dan pada
perlakuan D (NPK 1,5g/l : ZA 1g/l) -94,6g, selanjutnya untuk laju pertumbuhan spesifik diperoleh pada perlakuan A -3,72%, perlakuan B -2,84%, perlakuan C -1,47% dan pada perlakuan D -1,39%. Hasil penelitian ini tergolong belum layak untuk dijadikan rujukan dalam melakukan budidaya Gracilaria changii dikarenakan belum terdapat informasi mengenai dosis pupuk yang sesuai untuk menunjang pertumbuhan
Gracilaria cangii.
This study aimed to determine the effect of NPK and ZA fertilizer dosages on the growth of Gracilaria changii. The research was conducted from February to March 2025, spanning 35 days, in Totoli Village, Banggae District, Majene Regency, West Sulawesi Province. A completely randomized design (CRD) was employed, consisting of four treatments with three replications. Data analysis was performed using statistical methods in Excel. The results indicated that the applied dosages of NPK and ZA fertilizers were not effective in promoting the growth of Gracilaria changii in a laboratory setting. The absolute growth rates obtained were -173.6 g for treatment A (NPK 1g/l : TSP 1g/l), -156 g for treatment B (NPK 0.5g/l : ZA 1g/l), -100 g for treatment C (NPK 1g/l : ZA 1g/l), and -94.6 g for treatment D (NPK 1.5g/l : ZA 1g/l). Furthermore, the specific growth rates were -3.72% for treatment A, -2.84% for treatment B, -1.47% for treatment C, and -1.39% for treatment D. The findings of this study are not yet suitable as a reference for Gracilaria changii cultivation, as there is still a lack of information regarding the appropriate fertilizer dosages to support its growth.