Bests & Worsts Reviews from Amazon

I wanted others to know in no uncertain terms that this amount of Purigen (100 ml), as stated above, comes in its own bag, a fact not made crystal clear in the Amazon description. The other amount of Purigen 250 ml is just loose and requires the purchase of a bag. Also from the description, I got the impression that Purigen would consist of larger spheres, but the product actually is countless tiny pieces of fine, almost powdery bits that must be contained in a bag with very small mesh (only an issue if you get the larger amount of 250 ml). The product itself blows away the various carbon and resin products, which are the other alternatives. Like carbon, a tank with tannins clears right up with use of Purigen. It is certainly less messy to load in comparison with the grainy dust of charcoal smearing on countertops and sinks. In comparison to carbon, you also know when it is used up as it turns dark brown to black! Plus, it reduces the time required for filter maintenance, as you just glance at it in the filter to see the color rather than HAVING to change it every month or so as is the case with carbon and resin products that stop working at an indeterminate time. I have not yet cleaned the stuff with bleach and then soaked it in Prime, and I don't plan on doing it. I think that--rather than risk fish and amphibian lives with bleach in case it doesn't work--I will simply repurchase more Purigen! In my mind, the price is not so prohibitive that I am willing to take the risk.