Numerous studies suggest mental and physical health benefits of enjoying the outdoors. Deborah Cracknell, from Plymouth University (United Kingdom), and colleagues found that viewing aquarium displays led to noticeable reductions in blood pressure and heart rate, and that higher numbers of fish helped to hold people’s attention for longer and improve their moods. Observing that: “we found that increased biota levels were associated with longer spontaneous viewing of the exhibit, greater reductions in heart rate, greater increases in self-reported mood, and higher interest.,” the study authors submit that: “We suggest that higher biota levels … may be associated with important well-being and health benefits, particularly for individuals not able to access the natural analogues of managed environments.”
D. Cracknell, M. P. White, S. Pahl, W. J. Nichols, M. H. Depledge. “Marine Biota and Psychological Well-Being: A Preliminary Examination of Dose-Response Effects in an Aquarium Setting.” Environment and Behavior, July 28, 2015.