Many CAM plants stop opening pores when it gets over about 85 F / 30C at night. This can kill them within 1-2 days in hot-summer areas, like mine. I can't grow most Crassulaceae outdoors in summer. They collapse into piles of wet mush. Last summer (2020) we had 6 weeks of night temperatures over 85 F, and many hobbyists lost many large plants, of multiple succulent genera, that had been in the ground for years and years.
In cacti, cooler night temperatures do permit faster fixation of CO2 when the pores are open. But the plant can't store that much CO2 due to the internal pH falling as it is fixed. This is why CO2 supplementation at night in CAM plants doesn't speed their growth. (Daytime CO2 supplementation does speed growth in non-CAM, or C3, plants.) Most cacti have fixed as much CO2 as they can hold by midnight, and they have oxidized it completely by about 9 am the following morning. This leads to wide pH swings in cactus juices.
Cool night temperatures do seem to permit many plants to tolerate high daytime temperatures. But you don't have that issue in your controlled growing area.
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