Cryptic Zone Filtration

[jcw]

When I purchased the live rock from glassboxdesign's tank, he also sold me the rock in his cryptic fuge. It was the most colorful red, black and white rock covered with sponges and dusters and mushrooms. I recall he said he was dosing sugar directly on the rock.

Since then, I've added to my smallish 125g dt a 55g water reservoir that I filled 1/3 with live rock. Flow is slow and there is no light. I'm dosing vodka and vinegar into this. I hope to see some of the incredible life that was in his tank.

 

[mr.wilson]

I recall he said he was dosing sugar directly on the rock.

Sweet!

 

[tmz]

Every captive reef system has an area that "magically" develops sponges, tunicates, worms and other weird critters that seem to appear out of thin air...well, I guess water. They populate our overflows, protein skimmers, sumps, the undersides of rocks, and wherever else there's no competition. It's natures solution to an excess of something. In our case that excess is nitrate, phosphate, silicate and heavy metals (residual "bad stuff" from biological processes and nutrient import). Nuisance algae serves the same purpose, but with an ugly face and an overly competitive nature.


I don't think filter feeders sponges or other benthic animals adsorb or metabolize heavy metals. If they do could you point to some literature. I do think organic carbon is consumed by these non photosynthetic animals which is not included in your list. While some nitrogen is likely consumed along with some phosphorous, it is more likely to be reduced by bacteria via aerobic and anaerobic activity , whether in/on a sandbed or extra rock in the cryptic zone.

That said; I can't think of a downside to using one except perhaps an over reliance on it and consequent neglect of other important system needs. As part of a system I think they are helpful as habitat for benthic fauna and microfauna ; making more of it than that requires some data which is simply not available as far as I know.

FWIW

I use two cryptic areas on my system. One is a 50 gallon bottom fed top drained brute can full off live rock . The other is a bin full of live rock . Both are fed via drains from tanks in teh system and both have have significant sponge and feather duster growth. If nothing else they certainly add surface area for bacteria to colonize. I do suspect the sponges take up a good deal of organic carbon and spew off some cells that maybe useful food or at lest exportable via skimming or gac. I also use a remote deep sand bed and two chaetomorpha refugia,dose vodka and vinegar , run gac and a bit of gfo and skim well. All in all the cryptic areas are low maintenace additions which can be of some benefit to a system ,in my opinion, if adeqaute flow is provided to prevent anoxic conditions.

 

[mr.wilson]

Every captive reef system has an area that "magically" develops sponges, tunicates, worms and other weird critters that seem to appear out of thin air...well, I guess water. They populate our overflows, protein skimmers, sumps, the undersides of rocks, and wherever else there's no competition. It's natures solution to an excess of something. In our case that excess is nitrate, phosphate, silicate and heavy metals (residual "bad stuff" from biological processes and nutrient import). Nuisance algae serves the same purpose, but with an ugly face and an overly competitive nature.


I don't think filter feeders sponges or other benthic animals adsorb or metabolize heavy metals. If they do could you point to some literature. I do think organic carbon is consumed by these non photosynthetic animals which is not included in your list. While some nitrogen is likely consumed along with some phosphorous, it is more likely to be reduced by bacteria via aerobic and anaerobic activity , whether in/on a sandbed or extra rock in the cryptic zone.

That said; I can't think of a downside to using one except perhaps an over reliance on it and consequent neglect of other important system needs. As part of a system I think they are helpful as habitat for benthic fauna and microfauna ; making more of it than that requires some data which is simply not available as far as I know.

FWIW

I use two cryptic areas on my system. One is a 50 gallon bottom fed top drained brute can full off live rock . The other is a bin full of live rock . Both are fed via drains from tanks in teh system and both have have significant sponge and feather duster growth. If nothing else they certainly add surface area for bacteria to colonize. I do suspect the sponges take up a good deal of organic carbon and spew off some cells that maybe useful food or at lest exportable via skimming or gac. I also use a remote deep sand bed and two chaetomorpha refugia,dose vodka and vinegar , run gac and a bit of gfo and skim well. All in all the cryptic areas are low maintenace additions which can be of some benefit to a system ,in my opinion, if adeqaute flow is provided to prevent anoxic conditions.

If filter feeders, sponges and other benthic invertebrates don't absorb or metabolize heavy metals then we are wasting resources supplementing and including them in our salt mix.

"Most marine organisms can detoxify these materials (heavy metals) to one degree or another, but it takes time for the metabolic pathways which can do this (mostly the production of metallothioneins, the proteins used to bind and detoxify metals) to become active. This activation may take from several hours to several days."
Ronald Shimek PHD

Shimek measures heavy metal uptake by xenia in the same article and concludes that it is comparable, yet slower than caulerpa. Most hobbyists use Chaetomorpha in refugia which is a slower grower than caulerpa anyway. http://www.reefkeeping.com/issues/2002-12/rs/feature/index.php

Here's how he responded to the same question here on RC...
http://www.reefcentral.com/forums/showpost.php?p=883485&postcount=2

"By extracting particles from the water, communities of filter-feeding benthic invertebrates may have a beneficial effect on coastal water quality (Newell, 1988). Some ofthese animals (e.g. sponges) may even be able to filter and sequester other pollutants, such as heavy metals, as well as organic matter. Thus, artificial reefs supporting filter-feeder communities may be able to mitigate water quality degradation from organic enrichment (Figure 1). While this approach appears to have been adopted, for instance, in the Caspian Sea (Bugrov, 1994) and the Mediterranean Sea (in concert with the goal to produce harvestable sponges; Pronzato et al., 1999), quantitative studies of the ecological processes (individual nutritional physiology and biogeochemical cycling of organic matter and nutrients) and of the effectiveness of filter feeders on artificial reefs in improving water quality have not been published." ICES Journal of Marine Science
http://icesjms.oxfordjournals.org/content/59/supplement/S27.full.pdf


Tunicates are another story, as they are well known for their heavy metal uptake.

"Tunicate blood is particularly interesting. It contains high concentrations of the transition metal vanadium and vanadium-associated proteins as well as higher than usual levels of lithium. Some tunicates can concentrate vanadium up to a level one million times that of the surrounding seawater. Specialized cells can concentrate heavy metals, which are then deposited in the tunic. Wikipedia

Accumulation of heavy metals by some solitary tunicates...
http://ir.lib.sfu.ca/bitstream/1892/4744/1/b11994113.pdf

Trace element concentrations in some modern corals...
http://www.aslo.org/lo/toc/vol_16/issue_5/0786.pdf

and of course we have polychaete worms...
http://www.nrcresearchpress.com/doi/abs/10.1139/f82-022

and bivalves...
http://md1.csa.com/partners/viewrec...eavy+metal+uptake&uid=790785737&setcookie=yes

 

[tmz]

Well sure most organisms living in a world with heavy metals find a way to use or store them to some extent. I meant to add significantly to the sentence.

This activity,however,is likely not net removal activity, nor likely to be of enough magnitude to cite it as a benefit of cryptic zones . Indeed the interaction of some organisms with refractory organics in a cryptic zone might release more unbound metals than they take in. Exudates might also contribute unwanted elements to the soup.

Here are a few quotes from the same Shimek article cited in your post which give this point some context:

" What organisms are doing to these chemical balances in any given tank is open to supposition; no numerical data about any organism’s secretion or accumulation of materials are known from aquaria, and precious few of these data are available from natural reef areas. That organisms are manipulating their chemical environment is a given. However, reef aquarium concentrations of many of the dissolved trace elements are so different from actual marine concentrations that it is impossible to even reasonably speculate about what is happening in a tank. Simply put, there are too few data available to generalize."

"Materials that have been deposited by precipitation into the system’s sediment or by adsorption on to surfaces, or by incorporation into non-exported organisms are not removed from the system."

"Just about everything in a tank appears to be exported by skimming, albeit in often very low concentrations..."

"The organisms that modify the water the most are the bacteria and cyanobacteria (and some other microalgae) living in the tank. They may secrete materials that bind with toxic metals and make them insoluble, or by the action of their metabolism, they may lower the oxygen tension within sediments or porous rock resulting in the precipitation of some of the toxic trace metals as sulfide minerals or insoluble iron hydroxides"

Granulated activated carbon also removes some organic materials some of which undoultedly are bound to metals.

Thankyou, for the links . I'll look them over today.

 

[mr.wilson]

My comments about binding heavy metals were at the tail end of a list of benefits. The general conversation is about broadening the biodiversity of our captive reefs to emulate nature.

Tunicates are a major denizen of cryptic zones. As mentioned in the previous quote, tunicates can take up significant amounts of lithium and vanadium (up to 1,000,000.00 times that of surrounding seawater). Even if this is their only contribution to a closed system, it can be quite significant.

To put this into aquarium context, there are elevated levels of lithium in some supplements such as Kent Marine Tech-M Magnesium. Without water changes, tunicates may be the most efficient method of maintaining safe levels of certain heavy metals, even if they are merely bound, and not exported.

Exporting isn't the goal here, as we are assimilating "bad stuff"; just as a clam can polish the water without export.

 

[salty joe]

I wonder if a cryptic zone could be set up to provide sponge for 2 angelfish. I'm thinking 3 racks with 5-6 grapefruit sized rocks each and every other day put a new rock in. The rocks would have a month or so to regenerate sponge. Maybe that would give the angels a steady source of sponge. Maybe that little bit of live sponge suppliment would be helpful. What do you guys think?

 

[tmz]

I did not find any reference to tunicates and lithium in the posted links. I did find teh 1967 academic paper on vanadium and tunicates intersting but it doesn't make a case for vanadium removal by cryptic zone critters as a benefit

The author demonstrates that vanadium istakeuyp by some not all tunicates in their blood . Extrapolating that finding to a claim that cryptic zone critters bind harmful free metals in a significant way is a monumental leap the author never made.
Vanadium is used by many organisms ,for exapmple: the seacucumber holothuria,ntrogen fixingbacteriathat use it to form the enzyme ntorgenease in lieu of molydbenum or iron in some cases,rats and chickens for which it is thought to play a role ingrowth and reproduction.
So ,at nsw levels of only 1.8ppbillion or salt mix levels it isunliely to do harm and may be needed by organisms other than tunicates. Ideed it could be argued that horing by certainorganisms might be detrimental to others.

 

[tmz]

Salty Joe.
Growing sponges might be worth a try.It would be very nice if it worked . I'm not sure the sponges you might get would be the types your angels would favor or that growth would be copious enough to meet your needs .Dosing some silicate might help growth rates.

 

[tmz]

My comments about binding heavy metals were at the tail end of a list of benefits. The general conversation is about broadening the biodiversity of our captive reefs to emulate nature.

Tunicates are a major denizen of cryptic zones. As mentioned in the previous quote, tunicates can take up significant amounts of lithium and vanadium (up to 1,000,000.00 times that of surrounding seawater). Even if this is their only contribution to a closed system, it can be quite significant.

To put this into aquarium context, there are elevated levels of lithium in some supplements such as Kent Marine Tech-M Magnesium. Without water changes, tunicates may be the most efficient method of maintaining safe levels of certain heavy metals, even if they are merely bound, and not exported.

Exporting isn't the goal here, as we are assimilating "bad stuff"; just as a clam can polish the water without export. For clarification:
"Lithium is found in trace amount in numerous plants, plankton, and invertebrates, at concentrations of 69 to 5,760 parts per billion (ppb). In vertebrates the concentration is slightly lower, and nearly all vertebrate tissue and body fluids have been found to contain lithium ranging from 21 to 763 ppb.<sup id="cite_ref-enc_32-2" class="reference">[32]</sup> Marine organisms tend to bioaccumulate lithium more than terrestrial ones.<sup id="cite_ref-41" class="reference">[41]</sup> It is not known whether lithium has a physiological role in any of these organisms,<sup id="cite_ref-enc_32-3" class="reference">[32]</sup> but nutritional studies in mammals have indicated its importance to health, leading to a suggestion that it be classed as an essential trace element with an RDA of 1 mg/day. Observational studies in Japan, reported in 2011, suggested that naturally occurring lithium in drinking water may increase human lifespan.<sup id="cite_ref-42" class="reference">[</sup>


That is a quote from Wikipedia re; lithium.


I don't see it as necessarily "bad stuff ". It's actually classified a minor element, not a trace element in seawater at 174ppbillion. It's biological role is not fully understood but thought to be minimal. Most of it binds to other things readily as I understand it. It is used medically for treatments of bi polar disorder



BTW I've not been able to find any indication that Kent Tech M contains high amounts of Li. They claim only magnesium chloride and magnesium sulfate as ingredients. Impurities may be there but I don't know if lithium is and at what concentration.


Again even if certain tunicates take up some , and those tunicates happened to live in an aquarium's cryptic zone it doesn't mean that activity is a beneficial thing or a significant thing. Now if there is a cryptic ccritter that takes up free copper ,that would be significant.

Broadening the biodiversity and overall entrophy is why I choose to use cyrptic zones

In the 1982 textbook Principles of Biochemistry by American biochemist Albert Lehninger, for example, it is argued that the "order" produced within cells as they grow and divide is more than compensated for by the "disorder" they create in their surroundings in the course of growth and division. In short, according to Lehninger, "living organisms preserve their internal order by taking from their surroundings free energy, in the form of nutrients or sunlight, and returning to their surroundings an equal amount of energy as heat and entropy."

It's really not so much about export or assimilation as it is change and activity where certain inorganic non exportable substancess
can be made more bioavaliable,less toxic and perhaps more exportable via skimming and activated carbon

 

[DeathWish302]

All in all the cryptic areas are low maintenace additions which can be of some benefit to a system ,in my opinion, if adeqaute flow is provided to prevent anoxic conditions.

Tom,

Can you expand on

if adeqaute flow is provided to prevent anoxic conditions

? I'm an infant on a truly dedicated 'cryptic zone' and would like to know your turnover rate.

I've read anywhere from 0.1-1.0 cm/sec, but how does that translate to ratio of system volume/hr or gph? I've ran GAC before in my DIY reactor at about 75gph and the prefilter sponge has become anoxic after about 3 weeks when I forgot to rinse it after a WC. So, what's the optimal flow through my 20gallon? Is 100gph sufficient or should that be toned down to less?

I know this is very subjective, but I would like to know the general consensus on flow for a fully-cryptic zone.

Thanks!:beachbum:

 

[tmz]

I don't think a general specific optimal flow rate is clearly definable. Anoxia can develop when there isn't enough flow to deliver enough oxygen or nitrate to a localized area which sets the stage for sulfate reducing bacteria and hydrogen sulfide production as a by product. . Tightly packed or clogged rock or substrate loaded up with clogging detritus can create these zones.

FWIW. I use a covered 32 gal brute garbage can filled with larger pieces of live rock and spaces betwen them from the stacking . The water from a frag tank which also contains well s fed fish enters the bottom via a pipe plumbed from the top and flows out via a bulkhead near the top into the sump. The flow rate is about 400gph up through and around the rock . I also use a 50 gallon rubbermaid bin with medium and smaller pieces of rock spread out on the bottom only a few inches high . This also recieves about 400gph flow from a drain flowing from a chaeto and seahorse tank. Both have worked well( no clogs, rare need to clean, , etc). The bin has been in use for several years ; the can for over a year.

So I think flow combined with the structure to ensure water movement through out the rock is important along with monitoring for detritus build ups.

 

[DeathWish302]

I don't think a general specific optimal flow rate is clearly definable. Anoxia can develop when there isn't enough flow to deliver enough oxygen or nitrate to a localized area which sets the stage for sulfate reducing bacteria and hydrogen sulfide production as a by product. . Tightly packed or clogged rock or substrate loaded up with clogging detritus can create these zones.

FWIW. I use a covered 32 gal brute garbage can filled with larger pieces of live rock and spaces betwen them from the stacking . The water from a frag tank which also contains well s fed fish enters the bottom via a pipe plumbed from the top and flows out via a bulkhead near the top into the sump. The flow rate is about 400gph up through and around the rock . I also use a 50 gallon rubbermaid bin with medium and smaller pieces of rock spread out on the bottom only a few inches high . This also recieves about 400gph flow from a drain flowing from a chaeto and seahorse tank. Both have worked well( no clogs, rare need to clean, , etc). The bin has been in use for several years ; the can for over a year.

So I think flow combined with the structure to ensure water movement through out the rock is important along with monitoring for detritus build ups.

Thanks Tom!

I understand completely about the depletion of oxygen/nitrate and the resulting hydrogen sulfide. Just wondered if you knew of a 'rule of thumb' (or was that wrist) I didn't know about. Wish I had more room for a couple more Brutes, but I also like looking at the life so I opted for a glass tank.

I was not really buying the stagnant water flow rate with a cryptic zone, as I have found that my sponges, tunicates, & tube worms grow best in my raised bed rock pile in my sump and the DT. The lagoon is low flow for volume (1000gph in a 50gal) rubbermaid. The tube worm and sponges don't seem to grow at all in the areas that have minimal flow, but are covering rocks and the walls near the pump oulet. When I removed the lagoons 15' of return plumbing to the sump, it was filled with the 'red head' tube worms.

My sump has to be blasted with the baster every couple days to eliminate build-up, so I figured with a uber low flow rate the new cryptic zone would become a detritus magnet. I like detritus to create 'snowstorms', but when it starts building places difficult to dislodge it can become a problem. A sealed up cryptic zone would be exactly that.

Only time will tell.......

 

[tmz]

I think a lot of the life you can't see bacteria, protists and other microfauna are as important if not more so than the worms, sponges et alia.

 

[elegance coral]

The method is being dismissed by people like Dr. Ron, Eric Borneman, and myself not because it produces nitrogenous waste, but because it makes claims that ignore or completely go against basic biology. I've read most of Steve Tyree's work on the subject, and I've been less than impressed by all of it. He makes unsubstantiated and often ridiculous claims about these animals and their potential benefit to a reef tank.

What is the fundamental difference between Shemik and Borenman's little magic worms and pods, and Tyree's little magic sponges and tunicates? If Tyree's cryptic zone doesn't work, how is it that Shemik and Borneman's DSB does? They are both based on organisms that feed on tiny particles.

 

[mr.wilson]

DSB methodology promotes bacterial growth, while cryptic methodology promotes invertebrate growth. The two approaches share a common goal of increasing the biodiversity of reef tanks to be closer to that of a "natural system".

The crossover organisms between the two are the benthic inverts such as snails, worms, plankton and other infauna that occur in and near the substrate.

I don't think anyone is arguing that any one group of organisms are the key to success, but that a broad range of marine life provides a more complete ecosystem for assimilation and dissimilation of excess nutrients.

 

[elegance coral]

There are many different views on DSB methodology. I'm referring to Ron Shemik's DSB, where invertebrates play a major role. I don't see the fundamental difference between Shemik's inverts, and Tyree's inverts. http://www.ronshimek.com/deep_sand_beds.html

 

[tmz]

I think in both cases , DSB and Cryptic zone, the importance of the bacteria as part of the foodchain and for filtration via aerobic and andanaerobic digestion are usually understated and often misunderstood.

 

[DeathWish302]

There are many different views on DSB methodology.http://www.ronshimek.com/deep_sand_beds.html

I agree! BUT...even Ron makes the remark he 'recharges' his DSB infauna bi-annually. It's not a perfect system and neither is a cryptic zone. I would not dismiss either as a viable naturally occurring filtration method. Diversity is our only key to hinder extinction in such a small closed system.

I don't see the fundamental difference between Shemik's inverts, and Tyree's inverts.

I think the fundamental difference is one will process nitrogenous waste (DSB).

Regardless of what others' think, the addition of a few sq. ft. of unlit space either by means of a garbage can or blacked-out aquarium requires little effort or space. If it goes bad, it's easily unhooked. If the back of my tank and the bottom of LR is covered with sponges/tunicate/tubeworms, it obviously is a niche that these critters are capitalizing on. Why not add more?

 

[mr.wilson]

Adequate bacterial colonies alone can maintain Po4 and No3 at zero, but the vast majority of tanks require further reduction and export via other means of filtration.

Our hobby observations are largely superficial. We add a refugium and assume that if the Po4 and No3 go down it is due to export, while it is entirely possible that the algae culture is a site for denitrifying bacteria. We might even be doing more harm than good by disturbing biofilms while harvesting algae.

Having said that, there are lots of other viable sites for anaerobic bacteria in our systems and there are quantitative measurements of what algae can remove through export.

A mangrove planter would be a better zone to foster the growth of anaerobic bacteria. Mangroves grow too slowly to adequately export nutrients, but they do contribute greatly to the ecosystem method. Again, we are looking at the greater picture and not just one aspect of our systems.

I have heard a lot about DSB implementation, but the success stories aren't overwhelming. I'm not saying it isn't possible, but there aren't a lot of people out there that have been able to lower N03 from 40 to 0 with just the addition of a sand bed. Some of the anecdotal information out there is clouded with multiple system changes ie. a DSB was added, but at the same time detritus was removed and equipment was fine tuned, or the person simply spent more time on the tank during the effort. This isn't an anti-DSB comment or a claim that bacteria doesn't "work". I'm just pointing out that there are other practices that have a more direct cause and effect, such as carbon dosing which of course is a bacterial method.