Long-term worm storage at -70°C?

Does anyone have experience with long-term storage of worm strains at -70°C? We currently store strains at -80°C in our ultra-low temp freezer, but are considering a shift to -70°C in an effort to conserve energy. But before we do we would like to hear from anyone in the community that has done this, and whether the strains are stable and viable after long-term storage at -70°C.

Thanks!
Jeremy

Hi,

take a look at these threads…

http://forums.wormbase.org/index.php?topic=2044.msg4884#msg4884

http://forums.wormbase.org/index.php?topic=2156.msg5245#msg5245

Below -20 you enter the grey zone where folklore and myth come into play…I guess the answer is most likely yes…but the change in viability you’d observe between -70, -80 and -196 is probably offset by operator/equipment-introduced variations in viability (synchrony of L1 worms, strains frozen down, freezer characteristics etc etc.).

Steve