I would never waste my money on it. I was just wondering what the bacteria are contained in? What keeps them alive for shipping with no air exchange? It can't be just bacteria (one bottle would cantain enought bacteria to cycle a whole lake)
I ask because I got a lot of resistance to my "pre-cycled" filter idea. someone said the bacteria would not ship well, but people buy this biospira stuff all the time with no idea if the stuff is alive or what they're putting in thier tank. I'm pretty sure there is no regulatory agency looking at what is going into aquarium products.
I bought it ($30 worth) and it worked. I will buy it again. If your filter was kept in a vacuum packed package that was kept cold, maybe your bacteria would survive. It may be that they are putting food in the bag for the bacteria. I do not now what the seceret is, but Kasakto has it right, the stuff works.
It is refrigerated and dated, and the contents are named. It contains the actual species of bacteria which establish in FW tanks. One unit does not treat "a lake", it treats 30 gallons. A smallish container of bacterial spores could contain massive numbers of spores, but unfortunately the FW nitrification bacteria are not spore formers, so must be shipped in protective medium at low temperature as inactive vegetative cells.
And as others have already said, it does work. That is quite unlike the many other products which say that they cycle tank, but which do not not work.
There is no question it does indeed work. The question is was it always stored properly before you bought and used it. If you want to be sure get your tank set up and ready to go. Add pure ammonia and bring the level up to 4.0 on your test kit. Then add the bacteria and test again in 24 hours. If the bacteria in Bio Spira was viable (stored properly) the ammonia level should read zero. You then need to put your fish in immediately as the bacteria need the fish for their food source. There has been some excellent threads discussing this method of testing Bio Spira. Please check it out using the search function above.
The bacteria is probably kept in some sort of transport media. The cold temperature probably keeps the bacteria metabolism next to zero. It's probably stable at cold temperatures but breaks down at higher temps or the transport media breaks down.
Human serum samples with bacteria cultures or viruses are frozen and can be kept indefinitely. At higher temps the virus will break down.
If you aren't a scientist and don't know about culturing bacteria I think you'd be hard pressed to make a "cycled filter"