In this pilot study, we use co-located semi-hourly measurements of total dissolved inorganic carbon (DIC), total alkalinity, and the stable carbon isotope composition of DIC (δ13CDIC) over a 27 + h period from Tetiaroa Atoll, French Polynesia, to investigate the potential for reef carbonate chemistry to record information related to benthic photosynthetic community composition and response to natural gradients in ambient acidity and dissolved carbon dioxide.This dataset is included in the OA-ICC data compilation maintained in the framework of the IAEA Ocean Acidification International Coordination Centre (see https://oa-icc.ipsl.fr). Original data were downloaded from Mendeley Data (see Source) by the OA-ICC data curator. In order to allow full comparability with other ocean acidification data sets, the R package seacarb (Gattuso et al, 2024) was used to compute a complete and consistent set of carbonate system variables, as described by Nisumaa et al. (2010). In this dataset the original values were archived in addition with the recalculated parameters (see related PI). The date of carbonate chemistry calculation by seacarb is 2024-05-17.