Cryptic Zone Filtration

[mr.wilson]

Not quite true. To go back to the weed analogy, does the presence of weeds in your lawn mean that the grass couldn't have used all of the water you sprayed on it? No. All it means is that one species has some competitive advantage in using a resource. Sponges and tunicates are better at collecting bacteria than corals.

Water isn't an excess nutrient or resource for that matter. A healthy lawn, free of limiting pathogens and predators will fill all available space in the niche. A healthy aquarium with a strong population of benthic inverts in the substrate, will never have nuisance algae growth in the sand; however, the same tank can be plagued with algae on the glass. The only difference is the place in the sun left on the glass, free of competition. Certain weeds, or invertebrates in our case, will have a competitive edge, but not in areas in competition with display animals.

And how do you measure this in an uncontrolled experiment? It's also far from the only drawback. They're also turning beneficial bacteria into soluble nutrients, concentrating and releasing heavy metals, directly competing for food, etc. Meanwhile they are providing little to no obvious benefit. The things they're removing aren't things that need to be removed.

When I said "measurable", I'm working with the same limitation that we have for any "testing" in this discussion of methodology. One can measure the aesthetic appeal, growth rates, ease of maintenance, and operational cost. Beyond that, it's the unknown that keeps us in the hobby.

Clearly this is a false dichotomy. People have been running "natural" reefs for nearly 100 years without the help of fancy chemicals and mechanical filtration, and they never needed "benthic zones" to do it either. Plenty of people still run their tanks this way, including Eric Borneman, several locals I know of, and myself. Just because expensive, high tech reefs are what's been en vogue for the last 10 years or so doesn't mean it was ever the only other way.

I agree, a benthic zone doesn't have to be consciously created to exist in a captive reef. There are some hi-tech systems that have more detrivores and filter feeders than the most well intended cryptic or benthic efforts. My contention is that if you were to remove all of the worms, squirts, sponges, barnacles, and zooplankton, you would find that the hi-tech gear was of little use. Conversely, I believe that the protein skimmer and other chemical filtration could be removed with little impact on the system.

One of my observations is that a successful reef tank reaches it's prime only after a year or two, once the sand bed and dark corners are populated with benthic invertebrates. The protein skimmer, ion exchange resins, UV, and ozone had two years to achieve this goal that only time can deliver. The premise behind a cryptic or benthic zone is to speed the delivery of a stable ecosystem.

If you see no value in benthic invertebrates, and view them as parasitic, then why do you run a "natural system" yourself? What natural elements do you employ?

 

[mesocosm]

<a href=showthread.php?s=&postid=10198859#post10198859 target=_blank>Originally posted</a> by greenbean36191
Competitive exclusion only applies if the two organisms share a close enough niche and there is no disturbance. That's not the case here ...

Indeed ... :thumbsup:

See ...

Competition along a Spatial Gradient of Resource Supply: A Microbial Experimental Model.
C. T. Codeço and J. P. Grover
The American Naturalist
volume 157 (2001), pages 300â€"œ315

Trade-offs and coexistence in microbial microcosms.
Bohannan, BJ; Kerr, B; Jessup, CM; Hughes, JB; Sandvik, G
Antonie Van Leeuwenhoek [Antonie Van Leeuwenhoek]
Vol. 81, no. 1-4, pp. 107-115. 2002.

Off the hook â€"œ how bacteria survive protozoan grazing.
Carsten Matza, and Staffan Kjelleberga
Trends in Microbiology
Volume 13, Issue 7 , July 2005, Pages 302-307

Ecological stiochiometry, primary producer-decomposer interactions, and ecosystem persistence.
Tanguy Daufresne, and Michel Loreaua
Ecology
Vol. 82, No. 11, pp. 3069â€"œ3082.

Competitive coexistence in spatially structured environments: a synthesis.
Priyanga Amarasekare
Ecology Letters
Volume 6 Page 1109 - December 2003


HTH

 

[mr.wilson]

<a href=showthread.php?s=&postid=10199110#post10199110 target=_blank>Originally posted</a> by mesocosm Competitive exclusion only applies if the two organisms share a close enough niche and there is no disturbance. That's not the case here ...
Indeed ... :thumbsup:

HTH

False. That is the case here.

Benthic invertebrates would proliferate in the display tank if the corals were removed or if the nutrient import was increased.

 

[kolokefalo]

Greenbean,

I believe your statement is in conflict. You state competetive exclusion only applies if the 2 organisms share a close enough niche. The "niche" they share by your own statements is for their food. I would think this is a considerable "niche" to share since it is the most basic function of all organisms is the capture and processing of food. How can competitive exclusion not apply here?

Again, I am neither a college graduate, nor do I have any background in biology, chemistry, etc. However, I do read a great deal and have maintained reef tanks for 15 years and am quite familiar with the necessary knowledge to maintain and cultivate live corals. As soon as my youngest child (5) begins 1st grade I plan on returning to college for a degree in aquaculture offered here in Tampa at PHCC.

This thread kind of reminds me of the acrimony which existed for quite a few years between those who swore by algal turf scrubbers and those who were vehemently against them. It all breaks down to a few key elements:

How do you measure success in a reef tank?

Some measure their success by growth rates, coloring, variety, a number of factors. Some others measure the success of their tank by its ease of maintenance and not necessarily by being able to grow out an acro frag from 1" to 12" in 60 days.

I am definately in the school of ease of use. I believe setting up a tank with the ability to sustain itself with a minimum of "hands on/in" is my measure of success. If a benthic area can provide a function which helps eliminate detritus without having to vacuum the sump then it is already a success imho.

 

[greenbean36191]

Water isn't an excess nutrient or resource for that matter.

In terrestrial environments water is always a resource, and usually a limiting one.

A healthy lawn, free of limiting pathogens and predators will fill all available space in the niche.

I arbitrarily picked water as the resource, but the analogy works the same if you choose space. Does the presence of weeds in your yard mean that your lawn couldn't have utilized the space had the weed not been there? Still, all it means is that one species out competed the other for the available space.

I believe your statement is in conflict. You state competitive exclusion only applies if the 2 organisms share a close enough niche. The "niche" they share by your own statements is for their food. I would think this is a considerable "niche" to share since it is the most basic function of all organisms is the capture and processing of food. How can competitive exclusion not apply here?

Food is a resource, not a niche. A niche is the combination of all the resources an organism uses as well as how and when it uses them. You can have competition for a few resources without having much niche overlap, so no exclusion. The niche of antelopes and giraffes overlap when it comes to space and water, and both are herbivores, but because one feeds high in the trees and one feeds on the ground there is no exclusion (obviously though there are many more dimensions to the niche of both animals). It takes a fair bit of overlap to get exclusion. All of that goes out the window with disturbance such as diseases, predators, and environmental changes though.

Sponges and corals are only competing for space and food. Sponges can live in space corals can't. Corals can also eat food sponges can't. While the competition does put limits on resource use where they overlap, there are also resources available to one competitor and not the other that prevent exclusion.

If you see no value in benthic invertebrates, and view them as parasitic, then why do you run a "natural system" yourself? What natural elements do you employ?

To me they have the same value as fish. They're interesting regardless of whether or not they're of use in maintaining the tank. A tank would be easier to run if it had no fish, but it wouldn't be much fun to look at. Similarly sterile rock and no substrate would be less complicated, but is boring to me. My main area of study is reef ecology with an emphasis on inverts, so obviously I want as close to a natural invert community as I can get. However, I don't actively promote any of their growth except for the corals.

The filtration on my tank is just LR and a sandbed. The only mechanical filtration is an undersized skimmer. Most of the year I'm not around to take care of it, so the only maintenance it gets is a waterchange 3 or 4 times a year, top off, and minimal feeding. It's got everything from zoas to Acros. The only major problem it's ever had in the past almost 6 years now is last year when my brother, who was watching the tank for me tried to put an autofeeder on the tank while he went out of town. It fell in and the battery and the rest of the innards corroded in the tank. Surprisingly many of the corals recovered.

 

[mr.wilson]

A reef tank will never do as well without fish.

Fish play a vital role in coral health. They eat parasites, remove coral slime, provide Co2, and reduce food items.

 

[mesocosm]

Before I post another word ... excellent thread ! I appreciate the opportunity to rant about a concept which is so routinely mangled in reefkeeping discussion boards. That concept is ...Competitive Exclusion.

The competitive exclusion principle, sometimes referred to as Gause's Law of competitive exclusion or just Gause's Law, is a theory which states that two species competing for the same resources cannot stably coexist. Either of the two competitors will always have an advantage over the other that leads to extinction of the second competitor or an evolutionary shift of the inferior competitor towards a different ecological niche.

The basic reduction of this is simple enough, and most everyone makes it:
Competitive Exclusion ---> Extinction of one of the competitors

The thing is this ... there's another part that's almost always overlooked.

That part is this ...

... for reasons that are poorly understood, competitive exclusion is rarely observed in natural ecosystems, and many biological communities appear to violate Gause's Law.

http://en.wikipedia.org/wiki/Competitive_exclusion

Given that competitive exclusion is such a fundamental prinicple of ecology, it shouldn't be any surprise that researchers have focused alot of attention ... alot ... on why the competitive exclusion principle doesn't always appear to operate as would be expected. So much so that there's a classic example in the realm of marine biology: The Plankton Paradox.

It goes like this ...

All plankton species live on a very limited number of resources, primarily solar energy and minerals that are dissolved in the water. According to the competitive exclusion principle, only a small number of plankton species should be able to coexist on these resources. Nevertheless, large numbers of plankton species coexist within small regions of open sea.

http://en.wikipedia.org/wiki/Competitive_exclusion

As I said, much research has been focused on examining the difference between what is predicted by the competitive exclusion principle, and what is actually observed in Nature. The research database has evolved such that the reasons underlying The Plankton Paradox are becoming better understood ... hence the references in my previous post.

<a href=showthread.php?s=&postid=10199211#post10199211 target=_blank>Originally posted</a> by mr.wilson
... Benthic invertebrates would proliferate in the display tank if the corals were removed or if the nutrient import was increased.

Nolo contendre ... my point is that such proliferation is not endless, is not always unidirectional, and that new dynamic equilibria will become established. Additionally, the new dynamic equilibria need not have resulted in the extinction of any of the species from the original population.

<a href=showthread.php?s=&postid=10200232#post10200232 target=_blank>Originally posted</a> by greenbean36191
Sponges and corals are only competing for space and food. Sponges can live in space corals can't. Corals can also eat food sponges can't. While the competition does put limits on resource use where they overlap, there are also resources available to one competitor and not the other that prevent exclusion.

Yep ... :thumbsup:

If folks will take the time to skim through some of the references, they'll discover why greenbean36191 included the word 'disturbance' in a previous quote. Disruption can fundamentally alter competitive interactions, and perhaps most significantly ... niche and resource partitioning. Not meaning to be argumentative, but greenbean36191 is entirely correct about this stuff.

Such disruption need not be destructive, indeed, one of the phrases they'll come across is constructive interference (something that's almost never mentioned in discussions about competitive exclusion). I bring this up because folks utilizing cryptic zonation as a filtration strategy may wish to consider periodically disrupting segments of their cryptic zone in order to achieve higher productivity and greater biodiversity.


HTH

 

[kolokefalo]

I think we are in some way in agreement about this topic and merely viewing it from a different perspective. Even if the "cryptic/benthic" zone is not an "according to Hoyle" example of competitive exclusion, it seems we are in agreement of its role in the ocean as well as in an aquarium. It is merely a discussion of its merits.

Sponges can exist were corals can't- a true statement and as such they are placed in the sump devoid of light in order to proliferate.

Corals can receive nourishment from souces a sponge cannot ie. photosynthesis and zooxanthellae.

We are all in agreement about these things since they are fact. However, I believe we are on a tangent which is partly my doing in bringing up competitive exclusion. If this is not an example of competitive exclusion due to the "niche" overlap not being a major factor I am glad I learned a true and accurate definition of the actual law.

However, a cryptic/benthic zone does serve a purpose in creating a more natural reef tank when viewed through a larger prism of not only the coral reef but of the organisms which make up the elements of the entire reef ecosystem.

I apologize if that last sentence doesn't make much sense, I have a bellyfull of wine from going to my wife's boss' dinner party and had to ingest copious amounts of alchohol in order to be able to muster up the necessary "haha thats a good one" and " Oh man you are killing me" when he dropped another utter pantload of his excuse for humor. He asked me if I knew any jokes and I immediately thought "hrmmmm....do I go with priest and a rabbi walking down the street". Luckily common sense prevailed and I said " I can never remember them".

Great thread and I thank mesocosm, bean, and mr.wilson for the knowledge!!

 

[HBtank]

I just finished my sump and cryptic zone tonight.

I had two goals:

1. Add a significant amount of live rock rubble that was situated in a way that it was not a passive filter and water was forced through it.

2. increase biodiversity by creating benthic zones and refugia areas in combination with the rubble and DSB.

I wanted to also create something to hold my cheato directly under the light and I also wanted keep the surface of my refugiums DSB clear from anything. I tried to use as much egg-crate as possible to increase surface area throughout.

Here is a picture of it all.

The left has around 10-inches of rubble piled on an eggcrate support.

\

Here is just that section when finished:

This creates about 8 inches of rubble with no light, and 4 inches of area with eggcreate below it with no light.

The middle has a DSB with eggcrate right above it hanging on a shelf that also supports rubble on the edges (held in place by egg-crate) which also holds my cheato in place. The area above the DSB get a little light, but not much.

I do not use filter socks and think this setup will take full advantage of that food source, and in return keep my tanks diversity as high as possible, which is the main goal, and one that I think is very important. Diversity is fundamental in any ecosystems health.

But more directly, my wrasse love the mysis and pods, and I hope that in keeping other sessile invertebrate diversity high, I will hopefully continue my success with my linkia star which I enjoy very much. I have seen a definate pattern in its feeding and letting areas 're-grow', and hope this will increase my tanks capacity to grow any possible food sources.

Any other benefits, as discussed above are just icing on the cake.

I personally did not intend this to be any main addition to nutrient export. I use my skimmer, water changes, DSB and cheato for that. My DSB was already in place.

I think there could be some debate to this subject on different angels, though. As in my system, the lack of filter socks requires something to feed on that detrius and put it back into the water column for my main exports to work, so in a way it does provide this form of "helping" me export while providing food and increasing diversity.

 

[Vallen513]

HBTank. Nice DIY setup. I just built a new sump/filtration system myself. Includes a DSB, mangroves, macroalgae, skimmer, LR area. Light shines on the LR area. Thinking of covering it to make it cryptic. The biggest advantage as you and others stated is it is an area where particles drop into and get "cleaned up" my pods, sponges, worms, etc.

I think everyone here has made some very valid points. I would tend to agree that the cryptic fuge is not necessary. I think it also needs to be defined a little better. I think it brings to mind different ideas to different people. I have seen a few people's cryptic fuges be nothing more than a DSB with a few pieces of live rock on top. With the added factor of no light hitting it. I have seen others that are mostly live rock with no sand, and again no light.

I think one of the nicest advantages is that it serves as a great type of prefilter/filter. Especially for those of us who like Nature to take care of things for us, rather than a mechanical/human made solution. Rather than cleaning a sock or prefilter all the time, you can just let the overflow flow into the cryptic fuge where the various critters take care of the solid wastes.

I can see the other side, and type of people, who like a more unnatural/controlable setup. It takes up room that could be used for something else, and a pre-filter sock could do a better job? Just have to clean it.

In my experience there are those two ends of the spectrum. The one side being all natural filtration. The other end being as much "man made" as possible. It's really a preference of the owner though of which way to go. You can be sucessfull everywhere in the spectrum. I lean to the natural way, but still use a skimmer. Many others I know use the all "man made" way.
I just appreciate all the knowledge and experimentation in the last 15 years that have given many more possibilities and combinations of the "best" way for our own needs.

 

[Agu]

I bring this up because folks utilizing cryptic zonation as a filtration strategy may wish to consider periodically disrupting segments of their cryptic zone in order to achieve higher productivity and greater biodiversity.

If you've read "The Environmental Gradient" by Steve Tyree you'll realize that his cryptic zone aquariums were primarily holding tanks for his commercial venture. As such his tanks were hardly the static systems of the average aquarist. New corals and the biodiversity associated on live rock were introduced on a regular basis.

I'm not implying that a cryptic zone isn't a viable filtration model, I have one that's been working for a few years. Just want to point out that biodiversity can only be created by introducing new organisms to a system. The average aquarist with a show tank isn't introducing near the number of organisms as a commercial holding tank over any given period of time. As such, you can't expect to acheive the same results of Tyrees cryptic zones.


fwiw,

 

[gsxunv04]

I know this is an old thread but I am curious how all of your cryptic/benthic zones have worked? any notice in nutrient levels(increase/decrease in nitrates or phosphates?)
Thanks

 

[gsxunv04]

I know this is an old thread but I am curious how all of your cryptic/benthic zones have worked? any notice in nutrient levels(increase/decrease in nitrates or phosphates?)
Thanks

 

[CLINTOS]

<a href=showthread.php?s=&postid=9020132#post9020132 target=_blank>Originally posted</a> by Driftwood
I use a benthic zone in my sump. Very similar to a dark sump.

The live rock rubble & chaeto block most of the light, so the zone formed by the eggcrate is low light & low flow. I have had this running for about 2 months and so far it is a mysid factory, but not much for sponge/duster growth yet.

I've had great success with low blue light for colored sponge's

 

[tonyespinoza]

has anyone run any kind of cryptic zone for more than a year and have pics/details?

 

[CLINTOS]

<a href=showthread.php?s=&postid=10877120#post10877120 target=_blank>Originally posted</a> by Agu
If you've read "The Environmental Gradient" by Steve Tyree you'll realize that his cryptic zone aquariums were primarily holding tanks for his commercial venture. As such his tanks were hardly the static systems of the average aquarist. New corals and the biodiversity associated on live rock were introduced on a regular basis.

I'm not implying that a cryptic zone isn't a viable filtration model, I have one that's been working for a few years. Just want to point out that biodiversity can only be created by introducing new organisms to a system. The average aquarist with a show tank isn't introducing near the number of organisms as a commercial holding tank over any given period of time. As such, you can't expect to acheive the same results of Tyrees cryptic zones.

true I find once you introduce these organism's the regular dosing of phyto is very effective in multiplying them the thing that suck's is that it is risky it grow's the good bad and ugly my greatest advice is to start with a 20G 2- t5's blue/10 000k diy phyto and 1/4 cup of phyto daily and lot's of kenya tree's then extreme irratant removel and constant removel after adding 10 lb's live rock from there slowly increase phyto the natural filter with refuge slow will flourish you will be amazed indroduce in controled amount and the right scavenger's and you got yourself a protein skimmer free live food tank then you can add a small nemo size fish's no refuge because the 20G is the refuge then scrap the glass to feed after month's of preperation


fwiw,

 

[Agu]

"Originally posted by Agu
If you've read "The Environmental Gradient" by Steve Tyree you'll realize that his cryptic zone aquariums were primarily holding tanks for his commercial venture. As such his tanks were hardly the static systems of the average aquarist. New corals and the biodiversity associated on live rock were introduced on a regular basis.

I'm not implying that a cryptic zone isn't a viable filtration model, I have one that's been working for a few years. Just want to point out that biodiversity can only be created by introducing new organisms to a system. The average aquarist with a show tank isn't introducing near the number of organisms as a commercial holding tank over any given period of time. As such, you can't expect to acheive the same results of Tyrees cryptic zones.





true I find once you introduce these organism's the regular dosing of phyto is very effective in multiplying them the thing that suck's is that it is risky it grow's the good bad and ugly my greatest advice is to start with a 20G 2- t5's blue/10 000k diy phyto and 1/4 cup of phyto daily and lot's of kenya tree's then extreme irratant removel and constant removel after adding 10 lb's live rock from there slowly increase phyto the natural filter with refuge slow will flourish you will be amazed indroduce in controled amount and the right scavenger's and you got yourself a protein skimmer free live food tank then you can add a small nemo size fish's no refuge because the 20G is the refuge then scrap the glass to feed after month's of preperation


fwiw, "

I only posted the first two paragraphs, don't know where the phyto part came in

 

[Agu]

<a href=showthread.php?s=&postid=14993952#post14993952 target=_blank>Originally posted</a> by gsxunv04
I know this is an old thread but I am curious how all of your cryptic/benthic zones have worked? any notice in nutrient levels(increase/decrease in nitrates or phosphates?)
Thanks

Here's my cryptic zone on the far right,

It's not very big but I only have a ten over a ten setup. The chaeto on the top of the zone grows like the weed it is. It also keeps the rest of that side in the dark. That area is filled with pods, worms and featherdusters. I haven't seen any tunicates which are an integral part of Tyrees theory.

Have no idea what nitrates or phosphates might be, since there's almost no nuisance algae I don't bother to test for them. I only check specific gravity (salinity) and temp.

Disclaimer, I also do about 10% water changes weekly.

Non Disclaimer, I feed way more than the average aquarist but it doesn't seem to be an issue.

Bottom line I think it's working for me.

 

[guntercb]

Agu,

What light do you have over the sump? Also, what inverts do you have in the middle of your sump?

I checked out the photos on your link from the red house. What great looking tanks.

Cheers,
Chris

 

[Agu]

The light is two 26W curly PC bulbs in a really funky DIY fixture.

The two big corals are flower anemones. I suspect they're so big because of the constant supply of pods from the cryptic zone for them to eat.