Captain,

When I started using Purigen, my thought was, you don't get the maximum benefit if the water can flow around the media. I use an XP3 in my 26g tank and I cover the bottom of one of the media baskets with the Purigen so the flow has to go through the Purigen. I am using (4) 100ml bags. I know it is way more than Seachem suggests but I don't believe more is bad.... except for the wallet!

Mike