Why can I not store my strain at -80 degrees Celsius?

Although some cyanobacteria can be successfully frozen and thawed at -80 °C, other algae groups generally require storage in liquid nitrogen to remain viable.

At -80 °C, intracellular ice recrystallization can critically damage the algal cells. Cryopreserved strains must be kept at -137 °C or lower for long-term storage.