Water quality parameters (temperature, dissolved oxygen,
salinity, specific conductivity, turbidity) of each enclosure and the
cove were measured at days 0, 7, 14, and 21 (Table 1).
Water
quality measurements were taken semi-weekly at a uniform depth
of 0.5 m. In addition, Secchi depth of each enclosure and the cove
were monitored (Table 1).
Ammonia (NH4) concentrations were
measured from 100 mL samples collected at a depth of 0.5 m and
analyzed using a Flow Solutions IV Autoanalyzer (OI Analytical,
College Station, TX, USA) (Armstrong and Sterns, 1967).
Ammonia
levels were assessed relative to the US EPA’s current ambient water
quality criteria for ammonia (Harwood and Kuhn, 1970; USEPA,
2009) and were all found to be well below thresholds likely to
cause adverse effects to aquatic organisms (data not shown).