Treatments were created in eight 150 L tanks, each filled with 120 L of filtered (1 um) seawater that was changed partially (20%) every day (at ~17:00 h). Tanks were individually heated (300 Wheaters, Taikong Corporation) and chilled (Aquatech Ac11 or Shyeh Duwai Enterprise), with the temperature regulated using programmable, digital controllers (±0.1 °C, AquaControllers, Neptune Systems). Illumination was provided by metal halide (Phillips 150 W 10,000 k) and fluorescent (39 W, Phillips T5 460 nm) bulbs to create a mean light intensity of 268± 17 µmol quanta m-2 s-1 (±SE, n=64). The light intensity was selected to approximate that found at the collection depth of the parent colonies in March.
Treatments were created by blending CO2 with air, and continually assessing the mixture through an Infra Red gas analyzer (S151, Qubit Systems), which dynamically adjusted the flow of CO2 to maintain desired levels. The gas mixture was supplied through an air stone to four of the eight tanks, with others supplied with compressed air (i.e., ambient pCO2). The conditions in the tanks were analyzed for pH, salinity, temperature, and total alkalinity (TA) using standard operating procedures (Dickson et al., 2007), and the program CO2SYS (Lewis and Wallace, 1998) to calculate DIC parameters. The gas mixing technology and the methods for seawater analyses essentially are identical to those we have used before (see Dufault et al., 2012; Edmunds, 2011). In the present analysis, the calculated TA values of certified reference materials supplied by Dr. Andrew Dickson, Scripps Institute of Oceanography (batch no. 98 and 107), were determined within a mean of 1% of the certified value.
The incubation system created target temperatures of ~24.00 °C versus 30.50 °C, and target pCO2 values of ambient versus 86.1 Pa, and an irradiance of ~268 µmol quanta m-2 s-1. Conditions in the tanks were measured at least daily using a certified digital thermometer (Model 15-077-8, Fisher Scientific,±0.05 °C), a cosine-corrected quantum light meter (Li-Cor LI-192 attached to an LI-1400), and a sample of water withdrawn from each tank for pH, salinity, and TA analysis.
The 'ambient' and 'high' pCO2 levels: 49.4 Pa versus 86.2 Pa
The 'ambient' and 'high' temperatures: 24.00 °C [ambient] versus 30.49 °C
Data also available from PANGAEA: doi:10.1594/PANGAEA.823582
©2020 Biological and Chemical Oceanography Data Management Office.