Asparagopsis armata has international commercial relevance due to its high bromoform content, which can reduce the methane emissions from cattle when incorporated into their diet. However, few studies have reported on at‐sea cultivation techniques and their effect on bromoform content in A. armata. In this study, we assessed the effects of seeding density (150, 300 and 600 g WW m −1 ) on the specific growth rate (SGR) and brom...