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Calcified macroalgae are critical components of marine ecosystems worldwide, but face considerable threat both from climate change (increasing water temperatures) and ocean acidification (decreasing ocean pH and carbonate saturation). It is thus fundamental to constrain the relationships between key abiotic stressors and the physiological processes that govern coralline algal growth and survival. Here we characterize the complex relationships between the abiotic environment of rock pool habitats and the physiology of the geniculate red coralline alga, <i>Corallina</i> <i>officinalis</i> (Corallinales, Rhodophyta). Paired assessment of irradiance, water temperature and carbonate chemistry, with <i>C. officinalis</i> net production (<span style="" class="text">NP</span>), respiration (<i>R</i>) and net calcification (<span style="" class="text">NG</span>) was performed in a south-western UK field site, at multiple temporal scales (seasonal, diurnal and tidal). Strong seasonality was observed in <span style="" class="text">NP</span> and night-time <i>R</i>, with a <i>P</i>_max of 22.35 µmol DIC (g DW)⁻¹ h⁻¹, <i>E</i>_<i>k</i> of 300 µmol photons m⁻² s⁻¹ and <i>R</i> of 3.29 µmol DIC (g DW)⁻¹ h⁻¹ determined across the complete annual cycle. <span style="" class="text">NP</span> showed a significant exponential relationship with irradiance (<i>R</i>² = 0.67), although was temperature dependent given ambient irradiance  &gt; <i>E</i>_<i>k</i> for the majority of the annual cycle. Over tidal emersion periods, dynamics in <span style="" class="text">NP</span> highlighted the ability of <i>C. officinalis</i> to acquire inorganic carbon despite significant fluctuations in carbonate chemistry. Across all data, <span style="" class="text">NG</span> was highly predictable (<i>R</i>² = 0.80) by irradiance, water temperature and carbonate chemistry, providing a NG_max of 3.94 µmol CaCO₃ (g DW)⁻¹ h⁻¹ and <i>E</i>_<i>k</i> of 113 µmol photons m⁻² s⁻¹. Light <span style="" class="text">NG</span> showed strong seasonality and significant coupling to <span style="" class="text">NP</span> (<i>R</i>² = 0.65) as opposed to rock pool water carbonate saturation. In contrast, the direction of dark <span style="" class="text">NG</span> (dissolution vs. precipitation) was strongly related to carbonate saturation, mimicking abiotic precipitation dynamics. Data demonstrated that <i>C. officinalis</i> is adapted to both long-term (seasonal) and short-term (tidal) variability in environmental stressors, although the balance between metabolic processes and the external environment may be significantly impacted by future climate change.