I am going to be getting an FX5 kit with 500g of ceramic rings. From what I have read this is not enough to fill the center baskets with bio media. I have some blue bioballs from my sump and was wondering how good they will work in the center baskets of the fx5.
Do yourself a big favour and forget the bioballs in the fx5 ! They are extremely inefficient in a canister filter. Fill all your baskets with the most efficient bio media you can. The ceramic rings you have are ok, products like seachem matrix is better.
Ditto on Seachem Matrix. Bioballs are not designed for submrged use, and are not even a great option for what they are designed for. You are going with the best filter, go with the best media too. After all, you only need to buy biomedia once.
lots of folks seem to like the seachem matrix.. and i'm sure it's everything they claim. i personally prefer the ceramic bio-rings, i keep them in almost all of the baskets in my FX5's.