My gams survived in a little 4 x 8 x 1 feet holder frozen down to two inches. They can take a lot of abuse: temperature, oxygen, etc. They've been depleted a lot this summer in my main pond because the baby bass git em. I have a few thousand in that little holder...started with twenty-five from Amazon a couple years ago, after a water beetle cleaned out a few hundred rosy reds...I'd find forty deflated minnow skins every day...and then they were all gone. Nothing like a helgramite that eats a few every day, those beetles are killers.
