Blusink: Marine carbon removal

Blusink

Blusink: Marine carbon removal

Blusinkies lock away CO₂ via their material and coralline algae growth—boosting carbon removal, ocean resilience, and marine biodiversity.

London, UK

GBR

Hybrid of for-profit and nonprofit

—

The ocean is one of Earth’s most important climate regulators, absorbing about a quarter of all CO₂ emissions. But rising emissions are making oceans more acidic, disrupting marine ecosystems and threatening some of our most dependable benthic carbon sinks. As these natural systems weaken, so does their ability to protect us - from rising temperatures, food insecurity, and the escalating costs of climate change. At Blusink, we’re working to restore and accelerate natural ocean carbon removal systems - not just to help the planet, but to safeguard communities who depend on the ocean. Our Blusinkies are artificial pebbles that capture carbon in two ways: through their engineered materials and by creating the right conditions for coralline algae to grow. These algae not only store more carbon but also help build stronger, more biodiverse marine ecosystems that support fisheries, livelihoods, and coastal protection. Importantly, we do this in underutilised ocean spaces—so we’re not displacing communities, agriculture, or food systems. Instead, we’re turning overlooked seafloor into climate infrastructure. By boosting ocean resilience, we’re investing in a safer, more stable future for the millions of people whose lives and economies are tied to a healthy sea.

Our solution is based around Blusinkies - specifically engineered pebbles designed to remove carbon from the ocean while supporting marine biodiversity and resilience. They act similarly to artificial reefs, providing the exact minerals and porous structure needed for coralline algae to grow. Coralline algae beds are one of the oceans best mechanisms for storing carbon. Blusinkies remove CO₂ in two ways: - Material-based capture: The material that Blusinkies are composed of slowly reacts with seawater to change the distribution of bicarbonate, carbon and CO₂. This also gently raises local pH, helping buffer acidification and improve overall ocean resilience. - Biological acceleration: Their surface structure supports and accelerates the growth of coralline algae, which further removes CO₂ and builds resilient marine habitats. We’ve carefully designed Blusinkies to be unit-based and modular, allowing flexible deployment at different scales and ensuring we can conduct robust quantification of long-term impact. Their neutral, biomimetic design means they can be used in a wide range of geographies and support local species of coralline algae—enhancing ecosystems without introducing anything foreign. We believe climate solutions should do more than capture carbon—they should regenerate life, protect ecosystems, and benefit the communities that depend on them.

Our target population (beyond everyone on the planet who will ultimately be adversely impacted by rising atmospheric carbon levels) is predominantly coastal communities, particularly those dependent on healthy oceans for their livelihoods. This includes fishermen and women, aquaculture operators, tourism-based businesses, and local residents whose well-being is tied to thriving marine ecosystems. We know that many of these communities already feel the effects of ocean acidification, climate change and the decline of marine biodiversity - for example some of our partners in the Maldives have described the drop in tourism as a result of the health of their reefs. Likewise some of our partners in Colombia have noted the decline in fish populations and the increasing unreliability of their economic activity. As ocean ecosystems suffer, so too do the livelihoods of those who rely on the sea for food, income, and coastal protection. Despite their direct connection to ocean health, these populations are often underserved by traditional climate solutions and are not educated or empowered to take positive climate action. Our solution seeks to address this by providing these communities with both direct and indirect ways to generate sustainable blue-economy income, as well as providing education on ocean-climate interactions.