The dark treatment level
was held under a box beside the two other light treatments.
To perform the sunlight exposures, 600-mL
beakers filled with 500 mL of cell-free filtrate or ASW
controls were placed in their respective light treatment
level. The first sunlight exposure study was conducted
on 29 April 2009 at the Baylor Experimental Aquatic
Research (BEAR) facility, Waco, Texas, USA, for 8 h
beginning approximately 1 h after sunrise. Light intensity
was quantified throughout the study period with
Hobo U30-GSM Cellular Remote Monitoring System
(Onset, Bourne, MA, USA).