What exactly is the process that live rock performs?

[Horsey_Cat]

So Im well aware of the nitrogen cycle and how it works. I know that live rock and live sand work as biological filtration, but Im wondering in detail how it works. If I have 5lbs of live rock vs 10lbs of live rock does the 10lbs of live rock just help speed up the process of the nitrogen cycle? For example having more live rock is able to process ammonia faster and more efficiently than a smaller amount for example?

 

 

As a secondary question, I know xenia can be used for nutrient export because higher nutrients help xenia grow. But I heard for xenia to work effectively as a method of nutrient export you need to cut some xenia out of the tank and get rid of it. How does that work? Wouldn't more xenia just grow and since there's more of it to suck up more nutrients you wouldn't necessarily need to remove any unless you wanted to get rid of excess

[RayWhisperer]

In short, yes. More rock will speed up the process, and be able to handle a larger bio load. However, more rock also means more places fordetritus to settle. So, flow is another important factor to consider, especially when you've got tons of rock.

 

Anything living used for nutrient export needs to be harvested. That's the export part. Otherwise, all you are doing is binding nutrients. With a macro, it's pretty easy ti imagine. As the algae grows, older parts die off. This releases nutrients back into the water column. Xenia doesn't die off like that (perhaps over time it does, not really sure.) So, once you've filled a space with fully grown Xenia, how do you expect it to take up more nutrients? Harvesting allows more growth for more nutrient uptake. Now, I'm not sure how effective Xenia is vs a fast growing macro, like cheato. My thought is it isn't nearly as effective. Plus, that coral uses more elements when compared to your average macro. This means more dosing. Over all, macros are a far better option.

[Clown79]

I've had xenia in every tank. Never seen any difference on nutrient levels before or after addition.

 

I've actually have never heard of it being used as a nutrient export.

They use nutrients like all other corals do.

 

normally macro algae and mangroves for export.

[RayWhisperer]

Xenia filters are a holdover from the olden days. Same with aptasia filters. I've never tried either of them, but I'm pretty sure any fast growing macro would out perform Xenia, or aptasia by a long shot. The idea was a huge amount of them would have a significant nutrient uptake. It wasn't around for very long. I wonder why? Not really.