The impact of how ocean acidification (OA) will affect the biodiversity and functionality of marine ecosystems is very uncertain. Laboratory approaches are able to predict impacts at the organism level, however to scale up to marine communities studies it is far more complicated. A new project, funded by “Fundación Biodiversidad” of “Ministerio para la Transición Ecológica”, will explore these aspects of OA effects in the volcanic CO2 seeps off La Palma Island. In this incredible natural environments we can already observe how the marine ecosystems of the future looks like. The CO2 from volcanic degassing combines with the surrounding water, lowering its pH which mimics future conditions. One of these special places is located in the southern tip of La Palma Island, constituting by its accessibility and seeps features one of the most important natural laboratories in the world.