At what depth in a rock does anaerobic denitrification occur?

[danieljames]

Was reading a thread about using rubble as substrate, and was curious as to what the minimum size, thickness wise, a calcium based rock would have to be for any kind of efficient anaerobic denitrification to occur.

 

[Julio]

from what i understand this starts to occur just below the surface, i dont' depth is much of a factor.

 

[graveyardworm]

I think it would depend on LR density, and how many/what kind of critters are living within the rock.
Also using rubble for substrate I would think would be difficult to keep clean and would eventually lead to high nitrates.

 

[newreefman31]

danieljames since denitrifacation only occurs deep inside of a rock to detoxify toxins; would the people who have made there own rock be able to achieve the extra breakdown??? just some food for thought

 

[MCsaxmaster]

It can happen within a few hundred micrometers of the surface, maybe less. Denitrification happens in the centers of clumps of soil smaller than BBs or within fallen leaves in a stream. It usually doesn't happen very quickly relative to the loads on most aquariums though, so maximizing the area available for denitrification can be a good thing.

Chris