I like marinepure ceramic bioballs. I think they advertise each ball is equal to 240ft of surface area or something crazy. I gave it a shot on my 90g which I have been having success with; so I used them again on my 40b build.
I use good ole live rock rubble, rock and deep sand bed for biological filtration in my sump. All natural and nothing else and have had great success. I also use that approach in my 4, 10 and 14 gallon cube nano tanks.