Temperature was regulated in the
ambient tank using two 2-kW heaters and bubbling air ensured no temperature gradients occurred in the tank. The oxygen content in the chamber was measured
with a luminescent dissolved oxygen optode (Hach LDO, HQ40d, Hach
Company, USA) that logged dissolved oxygen recorded every 60 s. The
oxygen optode was housed in a separate 6-mL chamber, which received
seawater from the respirometry chamber via a recirculating peristaltic
pump (meacon Systems, TAS, Australia) at a rate of 12 mL min
−1
.