Originally Posted by Paul1792
No, the Purigen should be placed after mechanical filtration. You won't get enough flow anyway in the intake chamber and the Purigen will get full of gunk.
How big is your tank?
I suggest you use two 100 ml bags of Purigen ...... one in each filter. I have two bags of it in my Fluval C4 on my 29 gallon and one bag in each for my C3's in my 38 gallon. It is no more expensive to do it this way as each bag will last twice as long.
This is a 120 gallon aquarium, it has two ac110's, also one Filstar XP4 canister, and one Sunsun HW-303B canister.
I purchased the 250ml bottle along with two of the bags. I will use half in each bag and place one bag in two filters. Do you think it would be better to just open the canisters and place them in there?