It's sometimes known as the 'floating golden rainforest.' Large patches of a leafy brown seaweed called sargassum are often seen dotting the ocean surface, occasionally stretching for miles.
But in recent years, huge amounts have been washing up on coastal areas, smothering beaches with a rotting, fetid blob that can be hazardous to people and animals.
Now, a company in Scotland thinks it can solve two problems by sinking the Sargassum to lock up the carbon it contains in the deep ocean to help fight climate change. RAZOR's Neil Cairns went to find out how they plan to do it.