The environmental impact of keeping a tropical aquarium in Northern Europe

Abstract

Tropical fishkeeping is a popular practice in societies across the globe and involves recreating and sustaining an entire ecosystem in an aquarium within a domestic setting. The process invariably has an environmental impact, yet an assessment of this impact has previously been limited to the ecological consequences of harvesting fish from the wild or the release of non-native fish species. Provided here are the first estimates of carbon dioxide equivalent (CO₂ eq) emissions produced from running a tropical aquarium across multiple countries in Northern Europe (France, Poland and the UK), along with water consumption. Estimates were produced in silico and are discussed in the context of freshwater and marine aquariums, calculated using example aquarium sizes of 50, 200 and 400 l. Using estimates from the UK, depending on size and running conditions, a tropical aquarium produces an estimated 85.3-635.2 kg of CO₂ eq per year, equating to 1.6%-12.4% of the UK annual average household CO₂ emissions, and uses 156-31,200 l of water per year, equating to 0.2%-30.1% of the UK annual average household water usage. Despite this, comparison with the CO₂ eq of an average-size dog (127-1592 kg of CO₂ eq per year) or cat (121-251 kg of CO₂ eq per year), estimated from meat consumption alone, demonstrates that ornamental fishkeeping can be a more environmentally conscious pet choice. In addition, the majority of CO₂ eq produced from tropical fishkeeping is generated from the energy consumption of aquarium equipment and as more national electricity grids begin to decarbonize, this estimate should decrease.

Keywords: aquarium; climate change; electricity; emissions; fishkeeping; water consumption.