Not to cause disagreement, but maybe just as a side note? I saw a similar thread a number of years ago on another forum, and one of the engineering members did the calculations to prove that in fact bioballs have just as much if not more surface area than LR does. Since I'm not a math whiz, I can't even begin to tell you if the math was correct or not, but he certainly made it sound convincing and nobody argued with him
. At any rate, the surface area for anaerobic bacteria is certainly less.
I do know several individuals who have used bioballs quite successfully for many years, and one of the most important aspects of using them successfully is keeping them clean. Most I've seen recommend cleaning about 50% of them every month.
Like the others, I'm a fan of the LR rather than the bioballs, just had to throw it out there.