Biofloc Formation Performance in Seawater Using Different Carbon Sources As Initial Media for Fish Culture

Okto Rimandi Bakkara (Department of Aquaculture, Faculty of Marine Science and Fisheries, Raja Ali Haji Maritime University, Tanjungpinang, Kepulauan Riau, Indonesia)
Rika Wulandari (Department of Aquaculture, Faculty of Marine Science and Fisheries, Raja Ali Haji Maritime University, Tanjungpinang, Kepulauan Riau, Indonesia)
Daniel Sinaga (Department of Aquaculture, Faculty of Marine Science and Fisheries, Raja Ali Haji Maritime University, Tanjungpinang, Kepulauan Riau, Indonesia)
Muzahar Muzahar (Department of Aquaculture, Faculty of Marine Science and Fisheries, Raja Ali Haji Maritime University, Tanjungpinang, Kepulauan Riau, Indonesia)
Dwi Septiani Putri (Department of Aquaculture, Faculty of Marine Science and Fisheries, Raja Ali Haji Maritime University, Tanjungpinang, Kepulauan Riau, Indonesia)
Shavika Miranti (Department of Aquaculture, Faculty of Marine Science and Fisheries, Raja Ali Haji Maritime University, Tanjungpinang, Kepulauan Riau, Indonesia)
Jannesa Nasmi (Department of Aquaculture, Faculty of Marine Science and Fisheries, Raja Ali Haji Maritime University, Tanjungpinang, Kepulauan Riau, Indonesia)
Henky Irawan (Department of Aquaculture, Faculty of Marine Science and Fisheries, Raja Ali Haji Maritime University, Tanjungpinang, Kepulauan Riau, Indonesia)
Tri Yulianto (Department of Aquaculture, Faculty of Marine Science and Fisheries, Raja Ali Haji Maritime University, Tanjungpinang, Kepulauan Riau, Indonesia)
Tito Aria Nugraha (Department of Aquaculture, Faculty of Marine Science and Fisheries, Raja Ali Haji Maritime University, Tanjungpinang, Kepulauan Riau, Indonesia)
Veryl Hasan (School of Animal Science, Aquatic Science and Environment, Universiti Sultan Zainal Abidin, Besut Campus, Besut, Terengganu, Malaysia)

Jurnal Perikanan Universitas Gadjah Mada
Vol 28, No 1 (2026)

Biofloc technology has become a promising approach for maintaining water quality in intensive seawater aquaculture through the activity of heterotrophic microorganisms. This study aimed to evaluate the performance of the biofloc formation in seawater culture media using different carbon sources without starter inoculation. This study evaluated biofloc formation in seawater culture media using different carbon sources, namely molasses (control), wheat flour, rice flour, and tapioca flour. A completely randomized design with four treatments and three replications was employed. The research method employed a completely randomized design (CRD) with four treatments and three replications. The observed parameters included biofloc volume (Imhoff cone), absorbance value (optical density), plankton composition, and bacterial characteristics through isolation and Gram staining. The results showed that statistically, different carbon sources had no significant effect on biofloc volume (p > 0.05). However, descriptively, differences in performance among treatments were observed. The rice flour treatment exhibited the highest biofloc volume and absorbance value, indicating higher and more stable microbial biomass density, while tapioca flour showed the lowest performance. Microbiological analysis revealed the presence of Gram-negative heterotrophic bacteria, Gram-positive bacteria, and plankton communities consisting of phytoplankton, protozoa, and rotifers, indicating that the biofloc system had developed into a complex microecosystem. In conclusion, the type of carbon source influences the dynamics of biofloc formation, with rice flour recommended as the optimal carbon source to support biofloc system stability.