The YSI 6600 v2 Multiparameter Instrument, is designed for long-term in situ monitoring and profiling of CTD, pH, Chlorophyll,

The 6600 v2 is the only YSI instrument that can be deployed to 200 meters.  It uses standard YSI 6-Series probes, including YSI's Rapid Pulse stirring-independent dissolved oxygen sensor, and self-cleaning turbidity which is not affected by variations in ambient light.
 

It will log all of the parameters at programmable intervals and store 150,000 readings.  At 15-minute intervals, it will log data unattended for about 75 days.

	Range	Accuracy
Conductivity	0-100 mS/cm	± 0.5% of reading + 0.001 mS/cm
Chlorophyll	0-400 mg/L	± 0.1% FS
Deep Depth	0-200 m	± 0.3 m
Rapid Pulse DO	0-50 mg/L	circa 0.2 mg/L
ROX Optical DO	0-50 mg/L	circa 0.1 mg/L
pH	0-14 units	± 0.2 unit
Rhodamine	0-200 mg/L	± 5% of reading
Temperature	-5-50 °C	± 0.15 °C
Turbidity	0-1000 NTU	± 2% of reading or 0.3 NTU
Salinity	0.70 ppt	=1% of reading or 0.1ppt