There are many names for what is commonly referred to as "Probiotic Soda". They all are universally a Lactobacillus Ferment. Lactobacillus is a beneficial probiotic bacteria ferment as opposed to the more common yeast ferments of beer, wine, or cider. There are hundreds of lactobacillus sub species. Known collectively as Lacto-Ferments. Their main action is to produce Lactic Acid. A few species only produce lactic acid while the rest produce small amounts of alcohol, carbon dioxide (carbonation) as well as lactic acid.
Japanese Water Crystals and Water Kefir. identical in their production of the small bobbing pea size crystals that float up and down and congregate on the bottom. These are also known by hundreds of local names like; Tibi, Tibicos, California Bee's,... Typically we sell these by their dry form and are easily re-constituted. They are also easy to dry and store yourself when you wish to stop for awhile or to send to friends.
Ginger Beer PLANT and Jun are also a Lacto Ferment but produce a Kombucha SCOBY like structure. The main difference is that neither Ginger Beer nor Jun produce the Kombucha's Gluconic acid and most Lacto-Ferments produce higher levels of alcohol than does Kombucha.