A definition for " live rock".

[Belgian Anthias]

What about the planktonic uptake in the water column? Most live rock has some sort of bivalves, if they survive what about them? Macro algaes? Micro fauna? These all "filter" the water to some degree or another. That is why live rock works so well, because there are multiple avenues of "filtration".

All this can be achieved using rock which matches my basic definition.

 

[Belgian Anthias]

Porosity is critical, its why real coral skeleton is so much superior to fake concrete or mined limestone.

Why? Think about it this way. The rock itself is irrelevant and inert. What we are after are the Bacteria and Archaea that make up the microbial community. These live on surfaces, both the external surface and any internal surfaces.

A totally non-porous* rock has effectively zero internal surface area. A highly porous rock (coral skeleton) has literally thousands of times more surface area (**) because of all the internal cavities.

*I only consider pores that are large enough and reach the surface to be worth considering here. Technically concrete is "porous" in that water can soak in. But it doesnt have any internal spaces. Likewise, pumice has internal pores but they don't reach the surface. Coral skeletons are ideal.

** I pulled this number out of the air but I bet its a reasonable estimate.

I think to help the discussion we have to define" porosity"

For the definition, we need " usable surface"? "Usable surface", there where aerobic processes can take place?



Mined limestone can be reef rock from ancient reefs. Looking to it using x80 glasses a huge amount of pores are revealed, as will be de case looking at most chalkstone.
In practice, such stone can be broken down into smaller pieces, tumbled to round up the corners and then reconstructed to any desired form. It is then used for aquaculture of "life rock" or placed directly in the aquarium to be seeded with real corals and their holobionts, to become an excellent "life rock".

Ancient Reef rock not only consists of aragonite made by the calcification of corals but mainly of skeletons of algae (Halimeda?) coccolites, diatoms, and many other organisms.
Mined shell grit from ancient shell banks, or and coccolites, if looking to the surface with a microscope one will see huge pores.? if porosity is important, no reef rock is needed, porosity can be brought to you in the desired form.
In biofilters also maerl ( algae) is used.

Where I totally disagree is that the rock itself is irrelevant and inert. The substrate on which bacteria grow is very important for the filtration capacity of the biofilm. For example: in a nitrifying biofilm a lot of acids are produced lowering pH in the film. These acids dissolve calcium carbonate by which carbonate and everything else is released in the biofilm, and will be used as a carbon source instead of consuming total alkalinity.
A nitrifying biofilm growing on calcium carbonate or on glass or granite, it makes a huge difference and not only for what concerns the filtration rate.


In a normal nitrifying remineralizing biofilm growing on calcium carbonate substrate +- 15% of produced nitrate will be exported as nitrogen gas, mainly due to anaerobic remineralization using nitrate as an oxygen source. Such a biofilm has a high BOD, biological oxygen demand. Denitrification in deep pores may be responsible for

Denitrification does not support the carrying capacity of the system, the production of nitrate does.

That is why I connect"usable surface" to the water exchange rate.

 

[SMSREEF]

I really think it’s all about balance within the system you have. I also think the idea of porosity being needed for a bio filter is hogwash.

live rock makes it easier to balance a system because there will usually be a competitor to another microbe or organism that can get out of control. Even adding a few pieces of live rock to a tank with dead will help. It did in my tank.

Live rock will also will help in other ways. Some invertebrates found in the rocks may help recycle nitrate into ammonium that is used easier by corals and macroalgae. I’m sure I’ll get a little crap for this statement without a reference, so here it is. A study on tidepool diversity. https://escholarship.org/content/qt47t5n0vn/qt47t5n0vn.pdf

 

[jda]

So we are ignoring anything but bacteria? Sponges, pods, mini brittle stars all grow/populate better on porous rock compared to solid rock. This goes beyond biofilm.

 

[SMSREEF]

So we are ignoring anything but bacteria? Sponges, pods, mini brittle stars all grow/populate better on porous rock compared to solid rock. This goes beyond biofilm.

I don’t take your word for that. Sorry.

 

[HuduVudu]

 

[jda]

I guess if you don't know, then you don't know. At least remember this and come back and let us know when you do figure it out.

It is pretty much real science that corals and algae want to use ammonia/ammonium instead of nitrate - don't let any of the frontrunners and noobies on here that think that dosing N and P are feeding the coral bother you if they don't agree.

The issue with mined limestone is that it is usually bound with massive amounts of terrestrial phosphates and organics clogging up the pores. This makes local levels very hard for lots of sensitive things to grow as the phosphate unbinds and can concentrate into poisonous levels, similar to how local pH levels are lower than the rest of the tank. The binding is totally reversible once something removes all of the trapped organics, lets some water flow (slowly) and then allows the P to unbind into the water column. Seems like this takes a few years in most cases. Putting this mined limestone into the ocean seems to work since the ocean has very low P levels and the massive amounts of microfauna (beyond bacteria) can help work out those organics and get the rock phosphate-free (mostly) so that life can begin. Just the fact that this happens in nature, and in our tanks, should let anybody know that the deep down pores hold some meaning.

 

[SMSREEF]

I guess if you don't know, then you don't know. At least remember this and come back and let us know when you do figure it out.

It is pretty much real science that corals and algae want to use ammonia/ammonium instead of nitrate - don't let any of the frontrunners and noobies on here that think that dosing N and P are feeding the coral bother you if they don't agree.

The issue with mined limestone is that it is usually bound with massive amounts of terrestrial phosphates and organics clogging up the pores. This makes local levels very hard for lots of sensitive things to grow as the phosphate unbinds and can concentrate into poisonous levels, similar to how local pH levels are lower than the rest of the tank. The binding is totally reversible once something removes all of the trapped organics, lets some water flow (slowly) and then allows the P to unbind into the water column. Seems like this takes a few years in most cases. Putting this mined limestone into the ocean seems to work since the ocean has very low P levels and the massive amounts of microfauna (beyond bacteria) can help work out those organics and get the rock phosphate-free (mostly) so that life can begin. Just the fact that this happens in nature, and in our tanks, should let anybody know that the deep down pores hold some meaning.

I have referenced studies that show other invertebrates use nitrate and release ammonium.

Also, I referenced in other threads articles showing corals and macroalgae can use nitrate. Yes corals may use ammonia first, but that does not mean nitrate is useless.

So when you get off that high horse and open a textbook, or read a journal article, and reference them, then maybe I will listen to your craziness about nitrate and porosity.

 

[jda]

Here is how this usually works... people quit the hobby or they catch up and disappear from the boards. If you stick around long enough, you can put all of the layers together. You can be one of the first who comes back and acknowledges what they didn't know when they thought that I was a pompous butt while never yet having a tank with as much success. You might see then the actual help and experience that you cannot see now. Then, you can try and help with enough breath and depth of knowledge and experience to holistically make a difference instead of just referencing silos and stovepipes in a paper or article.

Here is the real truth that too few on this board what to hear. People who have been around, listed to actual PhD's talk for many years, read real books from actual vetted and qualified experts that survived the publication process, attended classes at real universities and then have applied all of this to actual successful tanks over a few decades have forgotten more than most people on this board with their papers, BRS videos and thread consensus will probably ever know. If the point is that I should just disappear to the private message boards with the rest of the truly exceptional reef keepers who don't have time to screw around with the thumb suckers, then indeed... I am getting more towards this every day since the the masses on r2r seem to value the easy answer and convenient truths.

A low to middling intellect will see all of this as an insult. An exceptional mind will see this as they do every other hard truth that anybody has ever give them... as the biggest kindness that people can offer.

 

[HuduVudu]

Here is how this usually works... people quit the hobby or they catch up and disappear from the boards. If you stick around long enough, you can put all of the layers together. You can be one of the first who comes back and acknowledges what they didn't know when they thought that I was a pompous butt while never yet having a tank with as much success. You might see then the actual help and experience that you cannot see now. Then, you can try and help with enough breath and depth of knowledge and experience to holistically make a difference instead of just referencing silos and stovepipes in a paper or article.

Here is the real truth that too few on this board what to hear. People who have been around, listed to actual PhD's talk for many years, read real books from actual vetted and qualified experts that survived the publication process, attended classes at real universities and then have applied all of this to actual successful tanks over a few decades have forgotten more than most people on this board with their papers, BRS videos and thread consensus will probably ever know. If the point is that I should just disappear to the private message boards with the rest of the truly exceptional reef keepers who don't have time to screw around with the thumb suckers, then indeed... I am getting more towards this every day since the the masses on r2r seem to value the easy answer and convenient truths.

A low to middling intellect will see all of this as an insult. An exceptional mind will see this as they do every other hard truth that anybody has ever give them... as the biggest kindness that people can offer.

My wife attended the last Sound Garden concert. She sat in the bleachers in the back. She enjoyed the music she enjoyed the show. In the front was the mosh pit (I know you know what that is ). These people usually didn't pay and they weren't there for the music. They were there to be seen and prove their manliness. Having been on stage (karoakee) I know what you can see from the stage through the lights. All that the guys from Sound Garden could see through the lights was the mosh pit. They never saw the huge numbers of people that were there to listen to their music and enjoy their performance. Nope, all they say was the crazy displays of pathetic manhood that took place in front of the stage. I have listened to early Sound Garden for years I never went to the shows because I didn't care for the performance. I just loved the music.

My first reactor was Knopp. I couldn't get it to work well. I gave up in frustration on it. I switched to plenums but you can't really grow fast growers with it. I have been working on the rabbit hole of calcium hydroxide with carbonation recently. I am interested in this rabbit hole but I think to myself constantly why not just do a CaRx with a plenum, and I remember back to the Knopp reactor. Then one day I read an article that I saw in the tag line of a guy on a post. That article gave information on calcium reactors and how to tune them. The light bulb went off and now I feel if decide to go back to try reactors once again I have a snowballs chance to be able to keep it going and stable.

I also know a guy here on the boards who just very recently bought a beautiful deep blue coral. That coral will be his pride and joy. I hope that he can keep it going. It is a good thing there was someone that knew how to grow it enough to actually make real frags for sale.

Jus sayin'

 

[SMSREEF]

Here is how this usually works... people quit the hobby or they catch up and disappear from the boards. If you stick around long enough, you can put all of the layers together. You can be one of the first who comes back and acknowledges what they didn't know when they thought that I was a pompous butt while never yet having a tank with as much success. You might see then the actual help and experience that you cannot see now. Then, you can try and help with enough breath and depth of knowledge and experience to holistically make a difference instead of just referencing silos and stovepipes in a paper or article.

Here is the real truth that too few on this board what to hear. People who have been around, listed to actual PhD's talk for many years, read real books from actual vetted and qualified experts that survived the publication process, attended classes at real universities and then have applied all of this to actual successful tanks over a few decades have forgotten more than most people on this board with their papers, BRS videos and thread consensus will probably ever know. If the point is that I should just disappear to the private message boards with the rest of the truly exceptional reef keepers who don't have time to screw around with the thumb suckers, then indeed... I am getting more towards this every day since the the masses on r2r seem to value the easy answer and convenient truths.

A low to middling intellect will see all of this as an insult. An exceptional mind will see this as they do every other hard truth that anybody has ever give them... as the biggest kindness that people can offer.

I was born in the 70’s and had a reef tank ever since I was I was 15. So we don’t need to talk about staying around.

If you think your patronizing self aggrandizement is helpful, think again. I’m definitely not buying it. In fact, it’s a little pathetic.

 

[Fish_Sticks]

If the point is that I should just disappear to the private message boards with the rest of the truly exceptional reef keepers who don't have time to screw around with the thumb suckers, then indeed... I am getting more towards this every day since the the masses on r2r seem to value the easy answer and convenient truths.

Enjoy your echo chamber - take the elitist attitude with ya and lock the door on your way out.

Somebody's upset and surprised people have other outlooks on reefkeeping than you do, on a public forum, who would have guessed?

A more progressive idea on reefkeeping, my own thoughts and ideas? No way, I'll just parrot what other people post and brag about how great I am.

Cant have a discussion without getting cranky and dumping your ego everywhere? Then buh-bye. Enjoy the echo chamber of dried out reefers who sit around parroting the same old things, day after day.

New ideas and theoretical discussions are too scary for some people - people who take discussions like they're a competition of sorts. Theres no 'winning' a forum discussion m8, only unless you go to the place where other people already think and parrot the same things as you.

 

[Paul B]

People who have been around, listed to actual PhD's talk for many years, read real books from actual vetted and qualified experts that survived the publication process, attended classes at real universities and then have applied all of this to actual successful tanks over a few decades have forgotten more than most people on this board with their papers, BRS videos and thread consensus will probably ever know.

Dam, I thought I was doing good until I read the part of attending classes at real universities. I missed out on that.

My wife attended the last Sound Garden concert. She sat in the bleachers in the back. She enjoyed the music she enjoyed the show. In the front was the mosh pit (I know you know what that is )

HuduVudu, I have no idea what that is, but i'm old and us geezers don't know about all this stuff. We just graze on the grass outside.

They never saw the huge numbers of people that were there to listen to their music and enjoy their performance. Nope, all they say was the crazy displays of pathetic manhood that took place in front of the stage.

I still don't know what this thread is about. I thought it was about rocks. I must be stupid.

And I thought my Manliness came about from being a combat Vet. But maybe I should go to one of those concerts instead.

By the way I was born in the 40s. That was before paper and dirt so we chiseled everything into rocks.

By the way, I love you guys and am just messing with you because I am waiting for dinner and am bored.

 

[CCauthers]

Good thread
I think there should be a chart for rock types as people get them a bit mixed up. Life and Live are not the same

Here is a partial list;

Dry
Dead (with junk on it)
Tanked (fake resin insert rock formation with rubber corals)
Life (dry with bacteria sprayed on it)
Cured
Live

Nice classifications. 100% agree, live rock comes from the ocean
I think that the arguing that is going on in this thread is a shame, because there are some quite accomplished and knowledgeable people here that just want to help, even if they can get irritated at some things.

 

[SMSREEF]

Nice classifications. 100% agree, live rock comes from the ocean

I agree 100%

But the problem is sellers, even some of the top ones call this stuff dry live rock.

and this stuff live sand.

 

[Fish_Sticks]

Nice classifications. 100% agree, live rock comes from the ocean
I think that the arguing that is going on in this thread is a shame, because there are some quite accomplished and knowledgeable people here that just want to help, even if they can get irritated at some things.

...at the risk of silencing any discussion or theories that don't feed an ego and drawn out routine - which one had zero involvement in creating, or advancing, and only regurgitates and practices on a discussion forum.

One instantly loses in reefkeeping when the first reaction is to shun new ideas, and assume total rightness about everything - especially if everything you know is not your own creation or take on things.

Open eyes and constant rethinking of how things are working, and, a constantly revolving reformation of our own ideas are essential to this hobby.

Otherwise, you might as well just be a robot or aquarium controller following a script.

The differences between a draftsman and an architect.

 

[Ksull72487]

In order to make it possible to distinguish and compare we must define what is considered “living stone”, we must define being alive. Any piece of rock placed in a biologically active medium, such as an aquarium, will soon become “alive”, covered with life.
To me, "living rock" is a piece of rock covered with what is called "periphyton" or "aufwuchs", it is covered with a mixture of dead and living growth of all kinds of organisms. The stone is covered with microbial mats, microbial communities. The added value must be sought in the origin of the stone, as it is transported over very long distances.
It is clear that when one speaks of “living rock” in the literature, they don't always talk about the same thing, especially when referring to “treated living rock”, so-called “cured live rock”.
A piece of living rock that meets my definition can therefore just as well be a piece of rock that has been in an aquarium for some time and has not been overgrazed. For my definition, porosity plays little or no role. The surface actually useful for biological processes is compared.

It would be interesting to know what is your definition of " live rock" and what would be the added value of such rock compared with my definition.

Awesome Question!!!!!!!!!! When I got back into the Hobby I said the same dang thing?

I always liked Fiji Live Rock. It means it came from the ocean. That’s my definition of Live Rock. And I can spot the stuff a mile a way.

Then you have Cultured Rock. Fake rock that’s been cycling at an aquatics store.

Then their is Dry Rock.

That’s how I look at it. Some stores have even said to me. This is Live rock. I’m like no that’s cycled rock. Others go we can get you some peices out of our tank. Umm okay where did it come from. Lol we don’t know one of our hobbyists. Okay so it’s cycled rock then.

Live Rock to me is living rock from a reef or ocean or rock that was from a reef or ocean in somebody’s home aquarium.

Cycled Rock is rock that is being kept wet to keep the bacteria. Fake or Unknown.

Dry Rock well that’s the stuff you find everywhere. That’s how I categorize it. But you are right it has got dang confusing these days.

Their was a time that fake cycled rock wasn’t purple and we couldn’t wait to get the coralline algae going. Lol now this is Carribsea Rock etc it has a coating. And we cycled it. Okay so it’s Cycled fake rock With a fake purple coating.

Their are three levels

Live Rock - Welcome the hitchhikers, but it’s real.

Cycled Rock - Ready to go and Probably Fake or Unknown and usually labeled.

Dry Rock - Youll need to cycle it.

Awesome question!

 

[Perry]

Ahh, dang, my non scientific, yet experienced mind must reply.
Porosity, is it important?
Well, sintered glass, aka, siporax, has been used in reef aquaria, for years. Pumice, also, has been used in the same fashion. The idea, is to promote copious surface area for bacteria to seed, dwell, and home. Typically used in a high export environment. If Porosity was not important, then why do these said medias exist? They replicate, but as mentioned, can never truly replace mother nature.
Edit, both media are claimed to by 10x more porous than rock.

 

[Paul B]

This is me collecting "live rock". It comes from the sea and is totally teeming with life inside and out.
Literally crawling with amphipods, sponges, worms, barnicles, trilobites and everything else in the sea.
I pick it up and throw it in my tank.
Of course this was in New York. I love New York rock because of the life especially the bacteria. Northern waters have multitudes more life then tropical waters although not all of it will live in a tropical tank. My tank doesn't seem to care. (the camera also adds ten pounds to what you actually look like)



But the tropical seas are built out of live rock as I am standing on here. I hope I am not crushing a starfish or parasite.

 

[Belgian Anthias]

Awesome Question!!!!!!!!!! When I got back into the Hobby I said the same dang thing?

I always liked Fiji Live Rock. It means it came from the ocean. That’s my definition of Live Rock. And I can spot the stuff a mile a way.

Then you have Cultured Rock. Fake rock that’s been cycling at an aquatics store.

Then their is Dry Rock.

That’s how I look at it. Some stores have even said to me. This is Live rock. I’m like no that’s cycled rock. Others go we can get you some peices out of our tank. Umm okay where did it come from. Lol we don’t know one of our hobbyists. Okay so it’s cycled rock then.

Live Rock to me is living rock from a reef or ocean or rock that was from a reef or ocean in somebody’s home aquarium.

Cycled Rock is rock that is being kept wet to keep the bacteria. Fake or Unknown.

Dry Rock well that’s the stuff you find everywhere. That’s how I categorize it. But you are right it has got dang confusing these days.

Their was a time that fake cycled rock wasn’t purple and we couldn’t wait to get the coralline algae going. Lol now this is Carribsea Rock etc it has a coating. And we cycled it. Okay so it’s Cycled fake rock With a fake purple coating.

Their are three levels

Live Rock - Welcome the hitchhikers, but it’s real.

Cycled Rock - Ready to go and Probably Fake or Unknown and usually labeled.

Dry Rock - Youll need to cycle it.

Awesome question!

You often use "fake"

In the case of " live" or "life" rock, what is fake? Making the difference between fake and not fake in a definition? You assume there is real "live rock" out there., which is not "fake" This must be a piece of the reef, harvested and packed without being in contact with air and delivered before ammonia builds up in the water before remineralization stops due to the biological oxygen demand.
Once at the surface most benthic organisms have exploded as they can not relieve the pressure in their cells. The bag will not contain air. What will be the effect of air on marine micro-live?
Even someone living at the shore of a tropical reef area will be delivered "fake".

Real " live rock "probably must be harvested very close to the surface? How many meters max?

Maybe real " live rock" only can be cultured in your own home?

Importing biological diversity or and microbial communities one does not need a piece of rock. If one wants fresh local tropical diversity it is possible to deliver it within 24h all over the world by plane, The weight of the rock can be replaced by life-supporting water. If not transported in a non-pressurized and minimal heated cargo of a Russian Antonov.
In most cases, the luggage area of planes is just kept frost free, lowering metabolism during transport, which can be good or bad. Live animals are transported on the flight deck, the place is limited.
A reason to transport " live rock" dry? I think the price will be the judge.

Dry rock? Packed in newspaper? Most marine microbial life is not able to make cysts to survive dry conditions, why should they? In their evolution of several million years, they never have been confronted with dry conditions.

What is "fake"?