What is a kind of fungus that grows more and granular in brown sugar water?

It is very likely to be Tibi, commonly known as the sun fungus.

Tibicos, Búlgaros, Japanese Water Crystals, California Bees) is a naturally delicious soda fermented with sugar water. Contains small amounts of fatty acids and caffeine. It is speculated that it originated in Mexico, as Mexicans like to drink a type of cactus.

Tibi is a probiotic.

A complex symbiotic cell that coexists with yeast. The benefits of Tibi are similar to those of fermented kefir with yacon, and are the best choice for those who wish to avoid dairy, such as vegetarians, or simply want to try another delicious taste! Sun mushrooms are a bit like yacon, and making sun mushroom soda is as simple as putting the mushrooms in sugar water and fermenting them at room temperature for 24-48 hours.

Yacon has many benefits for the body, among which diabetes.

Sick people can also drink it. It's much simpler than making yogurt, beer or wine, and it contains a lot of probiotics and beneficial substances.

Like most probiotics, it is said to be miraculous, and here I would say that a healthy human body itself is a well-structured, functionally magical tissue, and various internal organs work in harmony with each other and develop in harmony. If it is forced to add a large number of foreign substances, it is likely to cause the opposite effect, and each person's physique is different, and the impact of acid and alkali substances produced by various bacteria on the human body is also different.

Where can I buy this fungus?

You're talking about "kombucha". Here's what you need to know about it:

Kombucha is made from black tea (or with green tea, oolong tea, kuding tea, flower tea, etc.), white sugar (or rock sugar, honey) and water. The membrane of kombucha resembles the skin of a jellyfish, so it is called "Haibao"; Because kombucha can help digestion, ** a variety of stomach problems, so some places are called "stomach treasure"; Because kombucha is made from black tea and sugar into a bacterial liquid containing yeast, acetic acid bacteria and lactic acid bacteria, it is also called "kombucha". Kombucha is rich in nutrients such as vitamin C and vitamin B, and contains three kinds of microorganisms (such as yeast, etc.) that are beneficial to the human body, so it can regulate human physiology, promote metabolism, help digestion, prevent arteriosclerosis, fight cancer, maintain health and strengthen the body, and become a popular health care drink all over the world.

Kombucha has been circulating and applied in China for more than 150 years, and in recent years, the practice of using kombucha in the medical community at home and abroad has shown that kombucha can be used in a variety of chronic diseases, such as hypertension, arteriosclerosis, coronary heart disease, diabetes, constipation, hemorrhoids, obesity, alopecia areata, white hair, cataracts, rheumatoid arthritis, gastritis, dysentery, anemia, riboflavin deficiency, etc. But people must realize that kombucha is not a panacea for all diseases, and kombucha is only a nutritious drink after all.