Seachem Purigen

[fishy88]

got sum seachem purigen today was wondering what filter to put it in ive a juwel filter and a external would it matter what filter i put the bag in

 

[Malawi MaD]

Id put it in the external, they are more efficient than internals

 

[OldMan47]

I would put it on the shelf. Purigen is a strong chemical filter which is not really needed in any functioning mature tank. If you have a filter failure and must survive a few weeks until the new filter matures, maybe you would have a need for it. In that situation put it in the last possible position in the filter flow path. That way it will not interfere in your filter becoming cycled.