i was told at the pet store that if i added biospira to my tank that i could add fish immediately. i'm getting really bored of staring at an empty tank, my husband is getting impatient, and i cant find a filter from an established tank to float in my tank to speed up the cycling process. the filter my parents have on their outdoor pond is scary......there are actually earth worms living in it O.O and i dont know what other kinds of bugs and bacteria might be in it, so i decided to bypass that option, since i dont know anyone else with an established tank. its almost starting to sound like it would be worth the $12 to get some biospira to speed this thing up.