For pigment analysis 4L water was filtered through 25mm Whatman GF/F filters using gentle vacuum filtration with a pressure drop of less than 10 kPa. Samples were snap frozen in liquid nitrogen and stored at -80°C prior to analysis on land. Pigments were analysed using High Performance Liquid Chromatography (HPLC) according to the CSIRO method see Hooker et al. (2012) at the CSIRO laboratories in Hobart. For chlorophyll a analysis, 0.525 L of sample water was gently filtered via vacuum filtration (pressure drop < 10 kPa) on 25 mm Whatman GF/F filters. Chlorophyll a extractions were carried out following acidification according to Parsons et al. (2013). Samples were measured on a Turner Trilogy laboratory fluorometer.