| | Re: Purigen, matrix
Thanks for the post! Neither of those filter media's will remove your plant fertilizers. The Purigen is an organic scavenging resin, meaning that it only removes nitrogenous organic waste, while leaving all other elements behind. It is sometimes called a "protein skimmer in a bag", as a result of the amount of organics it removes from the tank.
The Matrix is what I like to call a "bacteria hotel", because it houses the beneficial bacteria needed for consumption of ammonia, nitrite, and nitrate.
I hope this helps!