Which would suggest that there is no particular advantage to Fritz over the others? (i.e. the one's that seemed to work) - based on this study. Because all over the forum on various forums one sees - well Fritz seems to work the best based on these studies - and (unless one believes as I do that true nitrifying cycle with nitrifiers i.e. Fritz is better than cycling with heterotrophs (@brandon429 ????). I guess I would make that clearer in the results.