I bought it from a store in the neighborhood because due to mishandling, the microorganism of my aquarium crashed and I saw the guppies visibly stressed. Specifically, I used oxygene to combat blue green algae/slime (I do not recommend it), but since my aquarium is a nano tank using the Walstad method without a filter, I didn't have any "yeast" of beneficial bacteria left to repopulate the water column. Even my snails had climbed to the surface and were trying to escape.

In less than 2 days, the water in my aquarium was the cleanest I had ever seen and the fish/snails returned to their normal behavior. Since then, I have been using it in every second water change/supplement for any possible situation. Gradually, the slime disappeared as these bacteria compete for nutrients (which is also mentioned on the product's webpage).

Very good for my case, although I suppose properly filtered aquariums, etc. may not need such remedies.