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Dissolved oxygen will be measured with a YSI ProODO or a YSI 556 MPS unit and results expressed in mg/Liter. Units will be air calibrated daily.

The oxygen transfer coefficient (KLa) will be determined by deaeration with nitrogen gas followed by aeration (0.60 slpm) using a YSI ProODO dissolved oxygen meter. The KLa value will be computed from the ASCE Standard for the Measurement of Oxygen Transfer in Clean Water http://cedb.asce.org/cgi/WWWdisplay.cgi?156576 The measured KLa values will be reported at 20C using a theta = 1.047.

Oxygen uptake of hauling water samples will be determined from the change in dissolved oxygen over a 30 minute period using a YSI ProODO dissolved oxygen meter. Sample will be stirred using a magnetic rod. Oxygen uptake will be determined by fitting a linear regression line through the dissolved oxygen vs time curve and expressed as mg/minute. The oxygen uptake rate will be reported at 20C using a theta = 1.047.

Following simulated hauling, fish from individual tanks will be transferred to 4 in diameter circular tanks for observation. Mortality will be recorded daily for 7 days.

Total ammonia nitrogen will be measured using an Orion Ammonia electrode, calibrated daily with standard solutions (0.1, 1, 10, and 100 mg/Liter), and results expressed as mg/Liter TAN

Un-ionized ammonia will be based on TAN, temperature, salinity, and pH. UIA will be computed from Tables 9 or 10 in http://fisheries.org/hatchery