When we can we try to offer sensors in different price and accuracy categories or for special purposes.
In the case of the DO sensors we offer a Galvanic cell sensor and an Optode. The galvanic cell sensor is less expensive than the optode but requires more routine maintenance to keep it operating effectively.
With regard to the fluorometers, our standard offering is either the Turner Cyclops-7 and the Seapoint fluorometer. The selection depends on the depth rating required 6000m or 600m and the range (µg/l) of the measurement (up to 150 µg/l or 500 µg/l), as well as pricing and power requirements. The Turner sensor is a less expensive sensor, but does have higher power requirements which would limit possible deployment life for deployments without external power supply to the instrument.