The Coastal Biogeochemistry Platform is housed at the Ocean Sciences Campus of the Nelson Mandela University in Port Elizabeth. The platform currently consists of a Seal AA3 nutrient auto analyser (to measure marine and estuarine water for SiO4, NO3-, NO2-, NH4+ and PO43-), a Milli-Q water purification system (to supply Type 1 Ultra-pure water), a Turner Designs fluorometer (to measure chlorophyll-a), a Hitachi UV-Vis spectrophotometer (to measure dissolved oxygen, pH and chlorophyll-a) and a Walz PHYTO-PAM fluorometer (to measure chlorophyll content and photosynthetic efficiency of microalgae). The laboratory will be expanded to also include a Flash Elemental Analyser (to measure nitrogen and carbon in sediment, organic material, seawater and on filters). The laboratory is operated by a dedicated team consisting of a marine biogeochemist, a laboratory technician and an intern. The laboratory accepts samples from all the SMCRI Sentinel Sites and affiliated research projects around the coast of South Africa. Close links have also been forged with other Research Infrastructures forming part of the SARIR, in particular the Expanded Freshwater and Terrestrial Environmental Observation Network (EFTEON) and the Biogeochemistry Research Infrastructure Platform.