i think if properly maintained the vases are fine
i had a betta once, i kept him in a vase for awhile, ultimately he went into a larger bowl (maybe 2 gal or little less). He lived for 6 YEARS!!
Bettas are hardy adaptable fish and can survive conditions that would kill most any other fish.Even so a 2-10g tank with good food is just good fishkeeping
i think if properly maintained the vases are fine
i had a betta once, i kept him in a vase for awhile, ultimately he went into a larger bowl (maybe 2 gal or little less). He lived for 6 YEARS!!
You can be kept in a small cage and be fed horse manure and the occasional meat scrap and live for several years as well. It would not be an enjoyable life, but you wouldn't die.