Refugiums don't export nutrients?

[xerophyte_nyc]

 

For Enzyme action on Marine Macro Algae check out this article ...

 

http://www.jstor.org/stable/2989956

Interesting. Algae have multiple ways to process different types of polysaccharides. Some species can handle starvation better than others via slower enzymatic breakdown of starch reserves.

 

The excerpt also showed a low level of algae oxidase and peroxidase activity. But we know this is minimal as evidenced by quick algae tissue degradation following topical peroxide application.

 

It seems to me these extraneous algae enzymes would work in conjunction with bacterial symbiosis. I wonder if there are any studies looking at algal interactions with associated bacterial biofilms?

[albertthiel]

Albert,

In my early years in this marvelous hobby, your website provided much insight into this passion of reefkeeping that has carried me on this journey that has lasted 40 years. I thank you for being a leader in providing understanding and knowledge. If you travel to Austin, Tx you have an open invite to tour my facility, AquacultureRanch. I always show Southern Hospitality, Cajun style.

La bonne temps roulee,

Patrick

 

Thank you for the kind words and the kindly for the invite and if I go head that way I sure will let you know. The website you are referring to was not kept up to date unfortunately by the new owners when I sold Thiel Aqua Tech but there are still quite a few interesting articles on it which can be found via the search feature on the top right of the main page.

 

One of these days I will have to start a new one ... but that will be for sure after my new book is finally on the market in a few weeks I hope. Currently still dealing with the publisher and formatting they require, and not exceeding the 500 page limit they put as a maximum for the book, and then creating a totally different format for the e-version, but all of that is what I am currently working on.

 

Thanks again .. I am glad to read that my site helped but even more so that your tank has been in operation for that long. There are not too many hobbyist around who have done so for that long (of course Paul B comes to mind).

 

Albert

[albertthiel]

It seems to me these extraneous algae enzymes would work in conjunction with bacterial symbiosis. I wonder if there are any studies looking at algal interactions with associated bacterial biofilms?

 

I am not aware of any but then I have not really done any research to determine whether I can find any. Working on the book and not much time left to do anything else really ...

 

If I happen to come across any I will post the link for sure here.

[xerophyte_nyc]

I am not aware of any but then I have not really done any research to determine whether I can find any. Working on the book and not much time left to do anything else really ...

 

If I happen to come across any I will post the link for sure here.

 

Any scientific work with biofilms is a major challenge because it is often impossible to experimentally replicate those conditions. It is definitely there. Every hard surface on the planet is colonized by bacteria. Rocks, leaves, skin, waterlines, you name it.

[Reefin Dude]

After reading your points, I realized the what you call increasing nutrients, I call increasing biomass. Coral, fish, macro, bacteria, janitors and detrivores all increase in mass. That is where the detritus goes. At some point, the biomass uses up all the available space and every thing crashes. I think that before the tank runs out of available water, the hobiest would have done something like prunning and removing biomass.

 

Skimmerless with no water changes for ten years..

 

There isn't a difference. Biomass is an increase in nutrients. This goes back to the point about looking at the entire system. The biomass would not be increasing unless the food source for the organisms is also increasing. There can only be as many organisms as there are resources to support them. If when the tank is new, those critters were not there, or in limited number, but now there are significantly more, then the system as whole has become more eutrophic. The levels of Pi may still read the same, but the total level of P has gone up because of all of the biomass.

 

If removing the biomass includes siphoning of the substrate, then we are all good. If removing biomass only includes removing algae, then there is a whole lot of P that is being ignored in the system, and the fact that the algae is growing is sign that the system has reached a trophic state capable of supporting. Whether or not that trophic level is what the aquarist wants is up to them, but having algae growing is only a good sign in certain emulated systems.

 

Some years back, Purina funded research that stacked pigs three tiers high. Only the first tier at the top was feed food. The second and third tier eat pig droppins from the above tier. The second tier gained the most weight with the bottom tier equal to the weight of the top tier.

By eating deritus the second level of pigs gained more weight than the first level which eat prepared food. Who was your source of info about eating another organisms poop not being efficient?

 

If the food fed to an organism is high enough in content, then I can see how a significant amount of the nutrient would go through the animal and come out as waste. How much do you poo after Thanksgiving? What would happen if they added a 4th tier? What do you think the results would be? If this really works, then why do we all not just eat our own poo? Wouldn't that make an organism 100% efficient?

 

Marine snow is a good example of end detritus in the open ocean.

 

G~

[tibbsy07]

There isn't a difference. Biomass is an increase in nutrients. This goes back to the point about looking at the entire system. The biomass would not be increasing unless the food source for the organisms is also increasing. There can only be as many organisms as there are resources to support them. If when the tank is new, those critters were not there, or in limited number, but now there are significantly more, then the system as whole has become more eutrophic. The levels of Pi may still read the same, but the total level of P has gone up because of all of the biomass.

 

If removing the biomass includes siphoning of the substrate, then we are all good. If removing biomass only includes removing algae, then there is a whole lot of P that is being ignored in the system, and the fact that the algae is growing is sign that the system has reached a trophic state capable of supporting. Whether or not that trophic level is what the aquarist wants is up to them, but having algae growing is only a good sign in certain emulated systems.

 

 

If the food fed to an organism is high enough in content, then I can see how a significant amount of the nutrient would go through the animal and come out as waste. How much do you poo after Thanksgiving? What would happen if they added a 4th tier? What do you think the results would be? If this really works, then why do we all not just eat our own poo? Wouldn't that make an organism 100% efficient?

 

Marine snow is a good example of end detritus in the open ocean.

 

G~

We don't eat our poo for many reasons, but largely because consuming the organisms within would be unhealthy for us in many cases. That being said, people who have Clostridium difficile infections are now being treated by literally consuming a "shake" of feces/gut flora from a housemate or family member as the healthy flora outcompete the C. diff.

 

There is a thing in agriculture in which the cattle, pigs, and chickens are rotated through the same areas one after another. The waste fertilizes the land and is also consumed by the following animals. It's actually a really interesting and sustainable farming practice.

 

For the biomass thing - I see what you're saying, but the reality is that if the nutrients increase and the organisms grow by consuming the nutrients, and it's all kept in balance then there isn't a problem. We keep discussing this as if the algae or bacteria will become "full" like we do - the reality is that they don't. They utilize phosphate in biochemical reactions. They will grow as fast as they can and will use the phosphates as fast as they can, as long as there is phosphate around. Our bacterial cultures in the lab will hit stationary phase, where they are dying as fast as they are replicating, once nutrients run out. If we spike the culture with new nutrients, they start growing all over again. If you keep feeding, they keep eating.

[coachfraley]

Can somebody summarize all 22 of the previous pages, lol.

[Reefin Dude]

We don't eat our poo for many reasons, but largely because consuming the organisms within would be unhealthy for us in many cases. That being said, people who have Clostridium difficile infections are now being treated by literally consuming a "shake" of feces/gut flora from a housemate or family member as the healthy flora outcompete the C. diff.

 

There is a thing in agriculture in which the cattle, pigs, and chickens are rotated through the same areas one after another. The waste fertilizes the land and is also consumed by the following animals. It's actually a really interesting and sustainable farming practice.

 

For the biomass thing - I see what you're saying, but the reality is that if the nutrients increase and the organisms grow by consuming the nutrients, and it's all kept in balance then there isn't a problem. We keep discussing this as if the algae or bacteria will become "full" like we do - the reality is that they don't. They utilize phosphate in biochemical reactions. They will grow as fast as they can and will use the phosphates as fast as they can, as long as there is phosphate around. Our bacterial cultures in the lab will hit stationary phase, where they are dying as fast as they are replicating, once nutrients run out. If we spike the culture with new nutrients, they start growing all over again. If you keep feeding, they keep eating.

 

But it is not kept in balance. It it were all kept in balance than their would not be any constant growth of any organisms other than the ones we bought. Any other increase in population points to an increase in total nutrients within the system.

 

In the bacterial cultures the population densities match the available resources. We are feeding our tanks everyday, or some every few days. This is new readily available Po for just about every organism. The poo that is produced is only readily available for a select group of organisms, and so forth. Every time more food is added and the poo is not removed, then the populations of all of the critters below the "top food consumers" increases, a net increase in nutrients for the system. If we start out with clean sand, then after a few months we have organisms in there, where did they come from if the system is balanced? If the systems are balanced, then why are we instructed not to stir a substrate? wouldn't it always stay clean if everything is balanced?

 

G~

[tibbsy07]

If you are getting an increase in the biodiversity in your tank, then no it's not in balance. However, if your organisms are getting bigger and nothing else is arising, then your tank IS in balance. Nutrients go up, organisms use more and they get bigger. As they get bigger they consume more and more, so as long as the rates increase at the same time, there isn't a problem. At some point, though, all established tanks balance out.

 

Balanced doesn't mean clean. Balanced doesn't mean it can't be knocked off-balance. It just means that everything is working symbiotically for the time. That's what we all want in our tanks. Sure, stirring up the sandbed makes things all wonky. Go into any balanced ecosystem and start stirring things up and see what happens.

 

There are a number of tanks with fuges who are not seeing increases in biodiversity. Their tanks are established and doing well. Others, not so much. There are also tanks without fuges that are doing really well. There are tanks without fuges that aren't doing well. Fuges aren't the answer, but they aren't the problem. Water changes are still the major nutrient export/replenishment system. All the other removal systems are icing on the cake. They support the water changes, but nothing can replace a water change.

[jestep]

Can somebody summarize all 22 of the previous pages, lol.

 

I was just going to post the same thing. I think the Po saturation in calcium based rock is one of the more important principles I've been able to gather in briefly reading all 23 pages. I also think it would explain the situation in a prior tank and why I am still growing GHA and bryopsis on that rock despite it not having seen light in more than 6 months with weekly water changes from my DT.

[albertthiel]

Those following this thread may be interested in a number of links I just posted to my thread on ULNS systems, on LNS ones and on pro an con views on such systems, as well as info and evaluation of a new product Nitra-Guard Titanium

 

The articles are via the link below which is to the first article, but there are several more in the posts after this one:

 

http://www.nano-reef.com/topic/305180-the-official-ask-albert-thiel-thread/?p=4190525

 

Articles are for informational purposes.

 

[coachfraley]

Some people like having a refugium and think that it helps their system by reducing nitrates and phosphates and providing diversity. Some people don't like having an refugium and think that keeping one will harm their system by raising phosphates.

 

There isn't enough conclusive evidence that either side is right because no one has ever actually studied this directly and the scientific evidence that does exist is not directly related to our enclosed reef systems.

 

So, you argue back and forth for 22 pages [edit: 23 pages] and never get anywhere.

Fantastic! You saved me an hour of my life, lol.

[Reefin Dude]

Some people like having a refugium and think that it helps their system by reducing nitrates and phosphates and providing diversity. Some people don't like having an refugium and think that keeping one will harm their system by raising phosphates.

 

There isn't enough conclusive evidence that either side is right because no one has ever actually studied this directly and the scientific evidence that does exist is not directly related to our enclosed reef systems.

 

So, you argue back and forth for 22 pages [edit: 23 pages] and never get anywhere.

 

I would summarize the 23 pages differently. Look at the system as a whole to determine the trophic level of a system instead of relying on a test kit that can only test for a waste product of waste product that in turn can be used by other organism and even the calcium carbonate. Look at the total mass of organisms. Everything from the critters in the LR and substrate, to the organisms that were purchased. These are the indicators of the trophic state of the system.

 

If you are getting an increase in the biodiversity in your tank, then no it's not in balance. However, if your organisms are getting bigger and nothing else is arising, then your tank IS in balance. Nutrients go up, organisms use more and they get bigger. As they get bigger they consume more and more, so as long as the rates increase at the same time, there isn't a problem. At some point, though, all established tanks balance out.

 

Balanced doesn't mean clean. Balanced doesn't mean it can't be knocked off-balance. It just means that everything is working symbiotically for the time. That's what we all want in our tanks. Sure, stirring up the sandbed makes things all wonky. Go into any balanced ecosystem and start stirring things up and see what happens.

 

There are a number of tanks with fuges who are not seeing increases in biodiversity. Their tanks are established and doing well. Others, not so much. There are also tanks without fuges that are doing really well. There are tanks without fuges that aren't doing well. Fuges aren't the answer, but they aren't the problem. Water changes are still the major nutrient export/replenishment system. All the other removal systems are icing on the cake. They support the water changes, but nothing can replace a water change.

 

As long as the organisms getting larger are the ones you want. Any other organism is just a sign of an increasing nutrient level. This is all about looking at the system as a whole and not at what the test kits are telling you. We need to learn to read the entire system. Confused how people that believe that their systems are cycling all of these nutrients emphasize biodiversity, but do not realize that biodiversity is just another bioindicator of increasing nutrients. Something that they are trying to defeat by having the biodiversity.

 

Nothing can replace a water change that aggressively goes after the detritus. Just changing water does little to affect the total nutrient levels of a system. Going after the source of the nutrients instead of waiting for the nutrients to be released. Removing the poo that Bluprntguy put in my pool with a siphon instead of just letting it sit there until it decomposes in order to feed the algae in the pool then removing the algae.

 

Those following this thread may be interested in a number of links I just posted to my thread on ULNS systems, on LNS ones and on pro an con views on such systems, as well as info and evaluation of a new product Nitra-Guard Titanium

 

The articles are via the link below which is to the first article, but there are several more in the posts after this one:

 

http://www.nano-reef.com/topic/305180-the-official-ask-albert-thiel-thread/?p=4190525

 

Articles are for informational purposes.

 

 

Reading through those links. They are still focusing on testing the water itself for determining what trophic state the system is instead of looking at the entire system as a whole. Reading the bioindicators instead of the test results. . Looking at Pi levels only gives one a tiny glimpse into the the total nutrient levels of a system. A Pi test kit is just a tool. We must understand what Pi is before we can understand what this tool is telling us. There is a big difference between 0, 0.0, 0.00, .... they would all read 0 on the test kits from 10 years ago. Yet people had algae. Algae is the bioindicator that the trophic level of the system is above what is needed for it to grow. It does not take a test kit that has the sensitivity to read 0.00001ppm to tell us this.

 

For the second article. Why is carbon limiting? He goes through all of the reasons why carbon is needed, but why is it limiting? If it is not for the fact that the bacteria are using it all up, then why? That article is so close to putting the pieces together, but still wants to ignore the 300lb gorilla hiding in the system (the calcium carbonate phosphate sink). Think about the explanation of why corals brown and how to correct it. How does this not play into what was being said earlier. Put the corals in charge of nutrient control and not the zoax. Feed the corals. The corals feed the zoax their waste products, and the coral benefits from the waste products back from the zoax. They are symbiotic for a reason. This is tightly held phosphate system between the corals and the zoax, with little new Po (captured food by the coral) added to keep the system going. They have evolved to live in a nutrient desert. Remove the source of the nutrients before it has a chance to become food for other organisms. SPS corals are not interested in Pi, they want Po. The coral will provide the Pi to the zoax.

 

G~

[Reefin Dude]

A good article about the basics of the symbiotic relationship.

 

Symbiotic Algae

 

G~

[albertthiel]

A good article about the basics of the symbiotic relationship.

 

Symbiotic Algae

 

G~

 

Yes interesting indeed. Thanks for posting it.

[Subsea]

 

There isn't a difference. Biomass is an increase in nutrients. This goes back to the point about looking at the entire system. The biomass would not be increasing unless the food source for the organisms is also increasing. There can only be as many organisms as there are resources to support them. If when the tank is new, those critters were not there, or in limited number, but now there are significantly more, then the system as whole has become more eutrophic. The levels of Pi may still read the same, but the total level of P has gone up because of all of the biomass.

 

If removing the biomass includes siphoning of the substrate, then we are all good. If removing biomass only includes removing algae, then there is a whole lot of P that is being ignored in the system, and the fact that the algae is growing is sign that the system has reached a trophic state capable of supporting. Whether or not that trophic level is what the aquarist wants is up to them, but having algae growing is only a good sign in certain emulated systems.

 

 

If the food fed to an organism is high enough in content, then I can see how a significant amount of the nutrient would go through the animal and come out as waste. How much do you poo after Thanksgiving? What would happen if they added a 4th tier? What do you think the results would be? If this really works, then why do we all not just eat our own poo? Wouldn't that make an organism 100% efficient?

 

Marine snow is a good example of end detritus in the open ocean.

 

G~

I can not let you say that increasing nutrients are the same thing as increasing biomass. Since we were talking about substrate, let us focus on increasing biomass in my Jaubert Plenumn substrate. As nutrients filter down thru the substratem bacteria populations are increasing expedentially. When these bacteria convert amonnia to nitrite to nirate to nitrogen gas, there is an element of nutrient export with the nitrogen cycle. All thru that process, I would consider the biomass no longer a nutrient until it decomposed and went back to basic elements. This comment can be brought up the food chain into the biomass of coral and fish.

As best as I can tell, you seemed to be fixated on inorganic and organic phosphrous. Let us talk one small phosphate cycle with macroalgae. Most macro algae will assimilate phosphate and nitrogen in 1:100 ratio. Some of the faster growing Caulerpas process phosphate 500% more phosphate. These fast growing macros assimilate in a 20:1 ratio of nitgrogen to phosphate. I did not read in the reasearch paper if the phosphate was organic or inorganic. I do know that macro will assimilate heavy metals from the water including iron and copper. It would not be much of a leap of faith to assume that macro will also assimilate inorganic phosphate. But to be blunt it really does not matter to me. As you stated in a much later post, the system bioindicators are what is most imporant. I always use bioindicators to determine system health.

Have a bodacious day,

Patrick

[penfold2]

When I started reading this thread I was dead set on using macroalgae as the primary filtration for my new tank. But after reading, I decided against macroalgae in my tank, and I just received my new skimmer today. I guess some of us found the ideas presented here more convincing than others. Here's a summary of what I got out of the thread:

 

Algae is not 100% efficient at sequestering P; it excretes a small amount. So even though algae can be harvested to create a net export of P, it is also ensuring that there is a small amount of P in the water column at all times. And the more P is being dissolved into the water column, the more likely it is to come into contact with calcifying corals before re-entering another sink. If we want to come anywhere near natural seawater nutrient levels, we need to eliminate as many P sinks as possible and get the P out of the system before it can enter the P cycle.

 

I would also like to thank FutureDoc and Reefin Dude for remaining so civil in the face of such adversity as was encountered here. I saw a lot of opportunities for this thread to devolve into personal attacks, and instead, they stuck to the topic at hand. I'm glad we could all rethink our assumptions, regardless of which side of the fence we ended up on.

[Nano sapiens]

Using algae growth and coral health/coloration/growth as 'bio-indicators' makes good, common sense. I believe that all experienced aquarists do this, either consciously or not.

 

I've been noticing comments such as "in an ULNS system with efficient detritus removal there won't be any algae", which implies that you don't need macro algae like Chaeto for nutrient export if you employ other means. Looking at an 'algae-free' tank and saying that it is that way due to being LNS or ULNS via efficient detritus removal (and likely other waste product removal processes) is correct, but is also missing an essential mid-part of the process.

 

On a typical, healthy oceanic reef with much lower NO3 and PO4 in the water column than in our reef tanks, if you physically exclude herbivores for any length of time macro algae will grow and eventually smother the corals on the reef. The best explanation I've seen for this phenomenon is that the algae are effectively, and very efficiently, using NO3 and PO4 (among other products) being liberated from the benthic community of organisms.

 

Considering that algae will grow in nature in such a pristine environment when herbivores are restricted, when we are looking at any tank with very minimal to no algae growth it would follow that the tank has been efficiently grazed of algae by the resident organisms. Would be interesting to know if anyone has completely removed literally all herbivores from an ULNS reef tank to see how the resident algae responded over an extended period of time (if algae do not grow, then we have a fundamental difference between the tank and the natural reef).

 

If a typical ULNS tank is 'algae free' (at least to our eyes) mainly due to the herbivorous organisms' algae consumption, as I believe it is, then we have conversion of algae bio-mass (which includes PO4, heavy metals, etc) into fecal pellets, which are then removed from the system either through mechanical filtering and/or or by direct vacuuming action of the aquarist on a regular basis.

[Reefin Dude]

I can not let you say that increasing nutrients are the same thing as increasing biomass. Since we were talking about substrate, let us focus on increasing biomass in my Jaubert Plenumn substrate. As nutrients filter down thru the substratem bacteria populations are increasing expedentially. When these bacteria convert amonnia to nitrite to nirate to nitrogen gas, there is an element of nutrient export with the nitrogen cycle. All thru that process, I would consider the biomass no longer a nutrient until it decomposed and went back to basic elements. This comment can be brought up the food chain into the biomass of coral and fish.

As best as I can tell, you seemed to be fixated on inorganic and organic phosphrous. Let us talk one small phosphate cycle with macroalgae. Most macro algae will assimilate phosphate and nitrogen in 1:100 ratio. Some of the faster growing Caulerpas process phosphate 500% more phosphate. These fast growing macros assimilate in a 20:1 ratio of nitgrogen to phosphate. I did not read in the reasearch paper if the phosphate was organic or inorganic. I do know that macro will assimilate heavy metals from the water including iron and copper. It would not be much of a leap of faith to assume that macro will also assimilate inorganic phosphate. But to be blunt it really does not matter to me. As you stated in a much later post, the system bioindicators are what is most imporant. I always use bioindicators to determine system health.

Have a bodacious day,

Patrick

 

You are again focusing on N, C, and O. These can be off gassed. It is P (phosphorus) that is the problem. It does not migrate upwards through the substrate. P is a part of all of that bacterial biomass. If the population is growing again it shows that there is a gain in P of the systems. When those other organisms or bacteria die, then how do those other elements besides C, O, and N get out of the substrate? This is the problem. We are thought to think that all elements are lighter than water and it all just floats away. This is not the case with P. It sinks, it has to be removed manually, even if you can not see it in a substrate.

 

Algae does not have a true root system. They are not able to uptake P from a substrate, they must get it through the water column. Part of what makes an algae and algae and not a true plant. There has been some discussion about using mangroves and turtle grass to pull P out of the substrate. Theoretically this is possible, but it still follows the problem of if it is growing, then the nutrients are there.

 

 

Using algae growth and coral health/coloration/growth as 'bio-indicators' makes good, common sense. I beleive that all experienced aquarists do this, either consciously or not.

 

I've been noticing comments such as "in an ULNS system with efficient detritus removal there won't be any algae", which implies that you don't need macro algae like Chaeto for nutrient export if you employ other means. Looking at an 'algae-free' tank and saying that it is that way due to being LNS or ULNS via efficient detritus removal (and likely other waste product removal processes) is correct, but is also missing an essential mid-part of the process.

 

On a typical, healthy oceanic reef with much lower NO3 and PO4 in the water column than in our reef tanks, if you physically exclude herbivores for any length of time macro algae will grow and eventually smother the corals. The best explanation I've seen for this phenomenon is that the algae are effectively, and very efficiently, using NO3 and PO4 (among other products) being liberated from the benthic community of organisms.

 

Considering that algae will grow in nature in such a pristine environment when herbivores are restricted, when we are looking at any tank with very minimal to no algae growth it follows that the tank has been efficiently grazed of algae by the resident organisms. Would be interesting to know if anyone has completely removed literally all herbivores from an ULNS reef tank to see how the resident algae responded over an extended period of time.

 

If a typical ULNS tank is 'algae free' (at least to our eyes) mainly due to the herbivorous organisms' algae consumption, as I believe it is, then we have conversion of algae bio-mass (which includes PO4, heavy metals, etc) into fecal pellets, which are then removed by the system either mechanically or by direct action of the aquarist on a regular basis.

 

Isn't this the way anybody with a nano is setting up their systems? The tanks are just to small to have the herbivores that are discussed in that article. It is one of those things that the algae people overlook when they read the article. The "herbivores" that can fit in a nano are interested in diatomic algae, not the algae that is discussed in the article. Nano-Reefers have been doing the counter to this article the entire time.

 

I have kept previous tanks without issue with only Trochus, Cerith, and Stomatella snails. These organisms just kept the diatomic algae under control.

 

The unfortunate part of that study. here it is again for all to read. Is that it dealt with the caribbean which is already under strong eutrophication pressure. It is hard to tell at the time of the study as to which came first, the herbivores or the algae. It could easily just be the fact that the reef studied was already borderline and the herbivores are keeping the reef just on this side of collapse. obviously just theorizing, but hard to tell otherwise from this article with respect to other articles about how algae is an indicator of eutrophication. Again shows the importance of understanding the articles presented. I did not see any values given for phosphates or nitrates in the article, so we are only led to believe that the area studied is oligotrophic because of the organisms present. If algae is present, then i would argue that the reef studied was not oligotrophic, but mesotrophic at best.

 

G~

[Nano sapiens]

Isn't this the way anybody with a nano is setting up their systems? The tanks are just to small to have the herbivores that are discussed in that article. It is one of those things that the algae people overlook when they read the article. The "herbivores" that can fit in a nano are interested in diatomic algae, not the algae that is discussed in the article. Nano-Reefers have been doing the counter to this article the entire time.

 

I have kept previous tanks without issue with only Trochus, Cerith, and Stomatella snails. These organisms just kept the diatomic algae under control.

 

 

 

G~

 

Perhaps you are not familiar with Nano tanks, but many deploy a small army of herbivores/omnivores. Hermit crabs, amphipods, snails, some small blennies, etc. Any of these will eat various types of micro algae and/or various types of macro algae.

 

I'm not referring to any particular article at this point, just elaborating on a theme you have continuously mentioned that a ULNS tank should have no algae if detritus is removed regularly, thus negating the need for Macro algae in a refugium. I agree with you, but I am also pointing out that algae is processed in any tank that has organisms that consume it, to a lesser or greater extent, and the PO4 is then removed via detritus removal.

 

In a system that maintains a higher nutrient level, then additional macro algae harvesting can be a beneficial tool.

 

This was fun and I hope everyone enjoys their nano reefs...whatever type they are

[xerophyte_nyc]

When I started reading this thread I was dead set on using macroalgae as the primary filtration for my new tank.

 

There's nothing wrong with macro, it can be implemented successfully for a variety of reasons. But as you stated, one of those reasons is not really as an export mechanism. I think what FD and RD want is for others to understand that concept. What you do with that info is a different matter. Not everyone wants a LNS.

 

Algae is not 100% efficient at sequestering P; it excretes a small amount.

 

At any moment in time, the excretion is small. Over time (days and weeks) the total excretion is actually greater than the amount thrown away from harvest.

 

And the more P is being dissolved into the water column, the more likely it is to come into contact with calcifying corals before re-entering another sink.

 

Organic P does not inhibit calcification - Pi does. But the extra Po feeds bacteria which convert it to more Pi. Since nothing is totally efficient, there is extra Po floating around which accumulates as detritus or binds to sand/ rock.

 

 

If we want to come anywhere near natural seawater nutrient levels, we need to eliminate as many P sinks as possible and get the P out of the system before it can enter the P cycle.

 

Or use the sinks to your advantage, and figure out how to purge them regularly. For ex, if there is an area in the tank where flow is low and it accumulates detritus readily, then this area should be vacuumed often.

 

 

I would also like to thank FutureDoc and Reefin Dude for remaining so civil in the face of such adversity as was encountered here. I saw a lot of opportunities for this thread to devolve into personal attacks, and instead, they stuck to the topic at hand. I'm glad we could all rethink our assumptions, regardless of which side of the fence we ended up on.

 

Civility goes out the window on certain topics. I find it to be funny actually.

[Subsea]

To further make the point about some misleading post and assumptions that macro algae do not uptake phosphate from substrate, I say this. The logic to the statement was that macro has no roots. No roots is true, but they do have holdfast. Without a bunch of bs, please tell me what comes up with the Calurpae Prolifera holdfast when I harvest from my mud filter. These holdfast go deep into this 1" muck. When I remove from tank, there is always black looking stuff coming up with many intricate hairlike holdfast. If the complete macroalgae assimilate nutrients from its surface area, would it not be prudent to assume that the holdfast surface area will assimilate nutrients that are concentrated in its immediate area. Remember, raw display tank water goes into this mud filter. That means detritus is in the immediate area of the nutrient uptake by Caulerpa Prolifera holdfast.

 

If we are open minded, let us not let our agenda or point of view stop us from being somewhat objective.

 

La bonne temps roulee,

Patrick

[penfold2]

There's nothing wrong with macro, it can be implemented successfully for a variety of reasons. But as you stated, one of those reasons is not really as an export mechanism. I think what FD and RD want is for others to understand that concept. What you do with that info is a different matter. Not everyone wants a LNS.

 

Yes, I should have specified that Acropora are a definite interest of mine, and I would like to have a tank dedicated more towards their needs than the needs of softies or other organisms from higher nutrient environments. I still think it would be really interesting to set up a skimmerless tank with a DSB, macroalgae, and some mud/detrivore kits from a few different places, and see what develops. I just don't want to compromise stony coral growth to see that. Maybe this is a good reason to set up another tank, lol.

 

Organic P does not inhibit calcification - Pi does. But the extra Po feeds bacteria which convert it to more Pi. Since nothing is totally efficient, there is extra Po floating around which accumulates as detritus or binds to sand/ rock.

 

Yup.

 

Or use the sinks to your advantage, and figure out how to purge them regularly. For ex, if there is an area in the tank where flow is low and it accumulates detritus readily, then this area should be vacuumed often.

 

That's what I consider removing a sink (detritus) before it can enter the P cycle.

 

Civility goes out the window on certain topics. I find it to be funny actually.

 

Certain topics are definitely catalysts for disagreement. But it literally took me 10 or 20 pages before I started coming around to the ideas presented here, so I'm glad FD and RD stuck to their guns.

[danimal1211]

When I started reading this thread I was dead set on using macroalgae as the primary filtration for my new tank. But after reading, I decided against macroalgae in my tank, and I just received my new skimmer today. I guess some of us found the ideas presented here more convincing than others. Here's a summary of what I got out of the thread:

 

Algae is not 100% efficient at sequestering P; it excretes a small amount. So even though algae can be harvested to create a net export of P, it is also ensuring that there is a small amount of P in the water column at all times. And the more P is being dissolved into the water column, the more likely it is to come into contact with calcifying corals before re-entering another sink. If we want to come anywhere near natural seawater nutrient levels, we need to eliminate as many P sinks as possible and get the P out of the system before it can enter the P cycle.

 

I would also like to thank FutureDoc and Reefin Dude for remaining so civil in the face of such adversity as was encountered here. I saw a lot of opportunities for this thread to devolve into personal attacks, and instead, they stuck to the topic at hand. I'm glad we could all rethink our assumptions, regardless of which side of the fence we ended up on.

First off no one here has made any claim that refugiums can provide 100% filtration for a thriving reef aquarium. Certainly using a skimmer is beneficial in many ways and good luck with your tank. The problem with some of the posts that have been made about macroalgae not being a method for nutrient export have been continually made without any substantial evidence to back them up. This has led to some comments that may seem more hostile, but are merely just the frustrations of those participating.

 

Its still seems that ReefingDude is taking some leaps of faith and writing them off under bioindicators. An increase in biomass in an aquarium is the goal isn't it? We want our pets to thrive and watching them grow is one of the best "bioindicators" of this. No one has claimed that refugiums somehow negate the need for aquarium maintenance, they are a piece of the puzzle and in many cases, a beneficial one. So what do you mean exactly by increasing biomass?

 

The claim that small polyp stonies can't survive long term in an environment with higher nutrient levels has also been made without any proof other than personal testimony. There are many long term success stories of SPS dominated systems, and the goal of NSW concentrations of nutrients is a unicorn. In the following link take a quick stroll down to photos 1 and 2 http://www.reefkeeping.com/issues/2002-07/eb/index.php. Photo 1 is of the typical outer reef crest where nutrients are at there lowest. But photo 2 shows an area of the inner reef where nutrients are much higher, micro algae are turning the water green and SPS are thriving. To say we have to maintain our systems as close to NSW levels as possible is certainly a no-brainer, but you're putting the cart before the horse. Why these regions of the reef so nutrient poor is because of the severe competition for these nutrients not because they are nutrient deserts.

 

Stating that Calcium Carbonate is a sink for phosphates is also well known in the hobby. Turkey basting your rocks routinely to remove detritus isn't a guarded secret. Once again it is suggested routine maintenance given in most beginners tutorials I have personally read. But you're beating around the bush again, are you suggesting we don't use Calcium Carbonate rock for reef structure? are you suggesting less live rock per volume? what is your point?

 

Your also making assumptions that algae can't survive in lower nutrients again without proof. We know from our own experience that this isn't the case. Hardy macro algae can survive in these conditions within our enclosed environments. Just because these aren't the environments they are typically found in nature, doesn't mean that its impossible. Further the abundance of herbivores on the reef crest is most certainly a "bioindicator" that algae can and will grow in these environments. Once again the fact that macroalgae isn't abundant in that environment doesn't mean it can't grow, its such a treasured commodity that it remains trimmed back and competition for every little bit is fierce.

[Subsea]

With respect to some good practical reefkeeping chores that would focus on phosphate/detritus removal, I have a technique that works well for my hi nutrient skimmerless Jaubert Plenumn 75G display tank with 30G mud/macro filter as a refugium. Because I view macro as my reefkeeping friend, I do not fret with a slight amount of red cynobacteria. When it gets thick enough to form a mat, much chemistry is happing in and under this mat. When this mat is vacumed out, I feel that it is much more concentrate with phosphate then pure "fish poop" before it is dissimilated into its parts.