Instrument: Airstone
Airstone - Also called an aquarium bubbler, is a piece of aquarium furniture, traditionally a piece of limewood or porous stone, whose purpose is to gradually diffuse air into the tank, eliminating the noise and large bubbles of conventional air filtration systems
Elevated CO2 levels were achieved via gas proportioners (ColeParmer) mixing air with 100% CO2 (bone dry grade) that was delivered continuously to the bottom of each replicate rearing container via airstone.