Welcome, glad to have you!
I'll agree with Bobby Re: the bio balls. I will say though, that
LR rubble can be just as bad. You'll need to keep it submerged, not in a
wet/dry area like you sometimes see bio-balls in, and you'll still need to blow the
detritus off the
LR rubble, or you'll still get an increase in
nitrates.
You've found a really great forum, with very friendly folks. We're allways happy to help however we can.