Low‐cost, high‐flow mesocosm system for simulating ocean acidification with CO2 gas

Abstract

The high cost of building and operating open‐flow experimental systems for studies of biological response to ocean acidification (OA) has led to extensive use of short‐term incubations in closed‐flow systems that do not simulate natural conditions. An inexpensive, highly reliable, open‐system that tracks natural diurnal and seasonal changes in water chemistry is described. This approach is based on a gravity‐feed seawater supply system that uses a peristaltic pump to regulate CO2 injection rate and a power head that cavitates the injected CO2 into microscopic bubbles that are dissolved immediately. This report describes low‐cost methods applicable to small or very large experimental systems. This methodology permits long‐term experiments under full sunlight with rapid seawater turnover rate that assures realistic environmental conditions in the experimental chambers.