Eric Borneman wrote a nice little article a while back about the Nitro cycle..
While true that LR doesn't lower nitrates itself, porous LR does provide surface area for anaerobic denitrifying bacteria to grow on. These bacteria, through anaerobic respiration, will breakdown nitrates into nitrogen gas and nitrous oxide.
That's what I was alluding to. I think it would take a large algae filter to do the same job as a big pile of LR
. I was speaking from practicle experience. I have one tank with a large amount of LR
and little algae and another tank with little LR
and a lot of algae. Zero nitrate in the first, lots in the second. While theory is a good place to start, other's practicle experience is invaluable. That's what I like about this forum.