ive decided to give this a shot. i read the back and it said that it has nitrosomonas, nitrosospira, and nitrospira which i believe are the bacteria needed for the nitrogen cycle. i added it to my tank then an hour later added 5 neon tetras. its been about 4 hours now. ill let you guys know what happens. i havent taken any water teests yet. maybe later but the tetras seem to be fine. they're schooling and swimming about. i might get 5 more because 5 is just a really sad school of fish but it dependis on if/ when i get shrimp and it still looks too crowded and such.