I have used the seachem one but not with enough regularity to notice any differences in my tank. Currently I'm using the FM UltraAmin product. Haven't noticed any differences with that one either. Kinda feeling a bit let down with the FM system, although it has killed off a goodly portion of the rampant brown wafer algae I was dealing with earlier in the year but that S on my forehead is like a beacon these days so I'll continue with it for awhile longer I guess
