This stuff is just amazing. I use it on my HOB filter for my turtle tank - crystal clear water. Amazing!
I use it in my 55 gal. tank which has 3 BIG goldfish, 2 juvenile goldfish offspring, loaches, corydoras, plecos and snails. The water is sparkling. I use a canister filter here and undergravel filter. When the water rod (jets) stop making a good hard stream of bubbles (telling me the hoses and filter are ready to be cleaned) I switch out to the second set of filter media and add itional Purigen filter bags I have ready. I can do a quick media change this way, while the Purigen soaks I have already got the filter back up and running. The benefits of having back up bags ready to go and extra filter pads.
I really like the recyclable facet of Purigen, it lasts much longer than using carbon and zeolite in my media bags. I assume it loses some of it's effectiveness, so I top-up the existing filter bags with new Purigen, and have added an extra bag to the mix as well. I have algae growing, which the fish eat, so obviously over filtration isn't an issue.
The water is crystal clear. Never has the water looked so good!
I have used purigen for a year and it's the so much more convenient than charcoal. I have 10 tanks and use purigen in all of them. I purchased enough so that when it's time for filter maintenance I can take out the exhausted purigen and just swap it for a regenerated pouch. Yes you can regenerate purigen by following the instructions on the package or you can Google how to do it. I personally have cleaned and reused purigen up to 5 times . You can tell when purigen needs to be fully replaced when it stays totally brown even with bleaching . It keeps my tanks cleaner longer. I highly recommend purigen.