YE, 30 degree (measured with TVS062CA, Advantec)
　　　　S. pombe   2.3 hours
　　　　S. japonicus         1.8 hours
　　　　S. octosporus        3.7 hours

We generally store cells at -80℃ in 15% of Glycerol in YE or EMM₂ media. Each round of freeze and thaw, they lose approximately 20% of viability, however, this was not improved in other concentration of glycerol; 0%, 30%, 40%. These concentration was tested, and did not see the significant difference in viability after several round of freeze and thaw. It should be noted that upon freezing using liquid nitrogen is NOT recommended as cells lose its viability a lot.