Maf 2500
Member
Totally agree with the above. Foam is an excellent media for bio-filtration which in combo with the substrate and plants in the tank is more than adequate.Only one sponge is not an issue. Your tank is well planted and all the heavy lifting of filtration will be done by your plants.
The cartridges that come with your original filter are borderline useless tat that is designed to block up after a certain amount of use forcing you to buy expensive replacements. Foam has the advantage of being 100% cleanable and with a very long service life (years).