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In the Andaman Sea internal waves of extraordinary amplitudes and frequencies break at the continental shelf and periodically introduce cold, nutrient-rich, hypoxic deep-sea water into the surface layer. The islands of the Andaman Sea shelter coral reefs from the effects of these large amplitude internal waves (LAIW) on eastern shores and separate them from the exposed reefs on western shores. Exposed reefs harbor corals with increased heat resistance, but which processes facilitate this resistance is not yet clear. As heterotrophic feeding has been shown to play an important role in warm water coral bleaching resilience and recovery, a shift in trophic strategy through LAIW-enriched organic matter flux may contribute to thermal resistance. In this thesis I utilized modern stable isotope and fatty acid analytics on separated coral host and Symbiodinium fractions to assess the trophic strategy of two coral species Porites lutea and Pocillopora verrucosa from both shore sites of two islands in the Andaman Sea (Miang and Racha). The results reveal a complex picture, with island and species-specific effects. Pocillopora does not show large differences in fatty acid trophic and health markers, with trophic markers indicating marginal higher heterotrophy on Rachas LAIW exposed but also on Miangs sheltered site. SIBER analysis on Pocillopora signals consistent trophic strategy on both sides. Porites do show a tendency of increased heterotrophy on Miangs LAIW exposed site and a smaller increase on Rachas exposed reefs. However, SIBER analysis of both islands pooled does not support this and instead indicates higher autotrophy. Health markers in LAIW exposed Porites are slightly elevated, in concert with higher biomass and fatty acids per surface they suggest a healthier phenotype. However, Pocillopora does not demonstrate this enhanced health status with LAIW exposure. As shift towards more heterotrophy seems to be nuanced and context-dependent it is most likely not the driving factor for the elevated heating resistance ...