Planted Tank Guru
Join Date: Jul 2010
Location: British Columbia, Canada
Yes, and get very fine mesh bags so the tiny Purigen particles don't escape into your tank. You can get 2 sizes of bags @ PetSmart stores (inexpensive) - but double-bag them to make sure the particles are contained properly. Don't layer the Purigen too thickly in the bag - no more than 1/2" thickness when laid flat, so that the water can flow freely through the Purigen.
Use the Purigen for not more than 2 or 3 weeks at a time - re-charge them after they become only medium-brown - don't wait till the particles get very dark brown/near black, as they'll have become saturated and have lost a lot of their effectiveness by then.
Follow the instructions for re-charging the Purigen (on the bottle label), rinse well and use conditioned water to do so, after the overnite re-charge in the 50/50 bleach &water solution. You can re-charge up to a dozen times before you need to get fresh new Purigen.