We don't recommend it because most people found it did either nothing or very little and in one case where the FC was allowed to go to zero to try and accelerate it, a conversion of CYA to ammonia occurred that created a huge chlorine demand. It is far too inconsistent and mostly ineffective to recommend using. It's not cheap and the risk of things going wrong and being even more expensive to fix is too great.
Even reviews on Amazon that are easily manipulated by shills reports 59% with 1 star while 36% that likely includes shills report 5 stars. Even if one were extremely generous and assumed that all reports were legitimate, it's still too inconsistent to recommend especially given its cost and that most of the time the reduction, if any, is small, and the risk of major problems if the bacteria stop at the conversion to ammonia which creates a huge chlorine demand.
Even reviews on Amazon that are easily manipulated by shills reports 59% with 1 star while 36% that likely includes shills report 5 stars. Even if one were extremely generous and assumed that all reports were legitimate, it's still too inconsistent to recommend especially given its cost and that most of the time the reduction, if any, is small, and the risk of major problems if the bacteria stop at the conversion to ammonia which creates a huge chlorine demand.