Pacific oysters (Crassostrea gigas) are an important aquaculture species due to their fast growth, high market demand, and adaptability to various environmental conditions. Triploid oysters, have an additional set of chromosomes relative to diploids, grow faster and are sterile, making them more marketable. Thus, triploids comprise a large proportion of this species grown worldwide. Triploid oysters, however, are reported to experience higher mortality rates than diploids. Growers must, therefore, make farm management decisions that balance the risks and rewards of growing triploids. Understanding how these stressors affect these oysters is essential, not only to understanding the drivers of triploid mortality but also to prepare for the impacts of climate change stressors on these individuals in aquaculture. In this study, we examined the impact of temperature, dissolved oxygen (DO), and pCO2 on diploid, chemically induced triploid, and mated triploid Pacific oysters. Diploid and induced triploid groups were full siblings, while mated triploids were half-siblings. We measured whole organism physiological responses—growth, mortality and dissolved oxygen—after a 4-week exposure to one of these stressors and an additional acute heat stress. Survival was high in all groups across a broad range of temperature and DO and temperature levels. Survival of mated triploids, however, was negatively impacted at lower (but still higher than ambient) pCO2 levels compared to the other two groups. Diploids and induced triploids had similar oxygen consumption patterns across temperature and pCO2 experiments, but diploids consumed more oxygen across all dissolved oxygen treatments. The differing performance of mated triploids suggests that their genetic background may contribute to their resilience or susceptibility to climate change stress. Thus, the development of locally adapted tetraploid broodstock production of mated triploid oysters is essential to the future of triploids in the aquaculture industry in a changing climate.