Our project is focused on the “integration of metagenomics, metabolomics, and lipodomics with chemical identification” using coral samples stored in the HML specimen bank collected from Maug submarine CO2 vent, Northern Marianas Islands. Multi-omic and chemical isotope analysis will be conducted on coral samples of three coral species (Porites lobata, Porites rus, and Pocillopora eydouxi) collected by R. Day and colleagues at low pH, mid pH, and high pH sites. The first step is to develop a standard protocol for multi-omic (genomic, proteomic, metabolomic) and chemical isotope analysis on coral samples. Then address changes in coral holobiont physiology (bacterial community and gene expression) across a natural pH gradient using this standard protocol.