Comparison growth of Kappaphycus alvarezii (Rhodophyta, Solieriaceae) cultivation in floating cage and longline in Indonesia

Currently, cultivation using cages for Kappaphycus alvarezii was limited reported before. This study aims to reveal growth of K. alvarezii cultivated in floating cages and longline. The study was conducted in one of cultivation areas in Southeast Sulawesi, Indonesia. Total gross weight, propagule growth rate and specific growth rate were performing in this study. During our field experiment, total gross weight of K. alvarezii after 40 days, from 5 kg was growth to 22.5 ± 1.40 kg and 38.8 ± 1.6 kg on longline and floating cages, respectively. Propagule growth rate after 40 days, from 50 g was 107.8 ± 7.0 g and 152.5 ± 7.9 g during April, and 132.0 ± 8.0 g and 218.8 ± 8.6 g during August, on longline and floating cage, respectively. Specific growth rate of K. alvarezii was high during August, 2.43% day−1 and 3.69% day−1 cultivated in longline and floating cage, respectively. Propagule morphology was white and damage in 40% cultivated by longline and no damage by using floating cage particular in August and September while high dense of herbivorous fish surrounding the experimental sites.