I like the sound of this Purigen (never heard of it before), especially the line in the seachem website which says "It polishes water to unparalleled clarity." I have been rather annoyed with the amount of suspended matter in my water of late so might give it a go. Its a bit pricey though. Do you need much of it?? As it appears to control nitrates maybe it could be added to a filter before taking a vacation to keep the nitrates down.