I recently pitched the old carbon cartridge from my Fx4, and I now have an extra basket in my filter. I want to add another media to the filter, but I'm not sure what I should go with. I have coarse and fine filter sponges in the first basket, and (I believe) zeolite in the second basket. I don't have a large fish load in the tank, just a few small fish. I do, however, have many, many plants. I'd like something that will polish the water similar to carbon, but lasts longer. Should I go with some filter floss, another set of sponges, or another solid media similar to the zeolite?
. What would be the best bang for my buck?
I was thinking of the rena xp4. Maybe it is a cross between the rena xp4 and the fluval 404.