Since "太岁" is composed of various types of 'fungi,' these fungi will disperse into the water, making the water infused with "太岁" beneficial to some extent.
Of course, whether these 'effects' are beneficial or harmful cannot be generalized.
So far, a few things can be confirmed. The poachers found this place using a special water sample; the water quality here is unique, not due to the waterfall outside, but because of the presence of "太岁" in the cave. The water in the cave flows through the pool where "太岁" resides, gets soaked by "太岁" and finally flows out of the cave into the large pool outside.
Secondly, the effects exhibited by this "太岁" are mostly positive. The "wild man" and the "Chinese Giant Salamander" must have been consuming the water steeped with "太岁" for years, resulting in the salamander's long lifespan and the wild man's robust physique and astounding recovery abilities.
This is also the most important point.