Limitations of DSB's

[cyberchef]

Originally posted by mojoreef
Well DOn thats not what I am hearing here. And you know me I love being the devils advocate.

NO WAY MIKE, NOT YOU....

The common idea that has been pushed by some not to be mentioned expert is that all detritus is processed inot some form of a gasious state, ie sulphide or N.

Maybe he's the one that ate the tacos...

Now we are being told that is isnt and that actually thier are alot of stuff left behind, one being end product detritus. So my questions stands what EXACTLY is being left behind and what does end product detritus consist of. Iwould also like to see some studies and or articles that show this. I want bullets people not daisys, lol

mike

Sorry Mike, I think we need Jerel in on this now.. I've never published a book so I don't have any "bullets" to throw around.. I've also never analysed fish S**T so I can't answer that either... Although I would presume that it's made up of whatever the fish had been chowing on...

Heh, just had an idea, lets feed the tacos and beer to the fish. Then we could use the lit match test (think of the movie "American Graffitti" I think) and prove that the end result is sulpherous or N gas...

[tdwyatt]

OK,

There is a reason that I have not taken a more active role in this entire debate, partly because I have been verbally discussing it (to death I might add) over the phones, and partly because there are SO many unknowns to the science that IS available (as I seem to keep finding out...). I have been doing some digging in the stacks (in ALL my spare time ) to see what substantiated info is out there.

First there is the area of how tightly do these substances adhere to Carbonate sediments? Secondly, what elements pose a threat, and to what extent, and how available are they to our corals in the wild? After reading all the misinformation and wild speculatioin on this topic, it is time to try and offer some unbiased legit information, let folks make an educated decision on how significant some of these issues really are. The following papers deal with reaearch in this area (these are the ones I have been able to procure, there are others in older and/or more obscure jorunals that are not available to me, as well as the stack that I have not even started to read. After all, Inter-library will only go so far... :

"Dissolution of Calcite in deep-sea sediments: pH and O2 microelectrode results", Archer, David, et. al.. Geochemica et Cosmochemica Acta Vol 53, pp. 2831-2845 Aug 9, 1989.

"Modeling the Calcite Lysocline", Archer, David, Journal of Geophysical Research, Vol.96, No. C(, pp.17,037-17,050, September, 15, 1991.

"Equatorial Pacific Calcite Preservation Cycles: Production or Dissolution?" Archer, D. E., Paleoceanography, Vol 6, NO 5, pp.561-571, Aug, 1991.

"Distribution of Carbonate in Surface Sediments of the Pacific Ocean," Berger, W.H., Adelseck, C.G., Mayer, L.A., Journal of Geophysical Research, Vol 81, NO 15, pp. 2617-2627, May 20, 1976.

"Distribution of Calcium Carbonate in Surface Sediments of the Atlantic Ocean," Biscaye, PE, Kolla, K, Turekian, Journal of Geophysical Research, Vol 81, NO 15, pp. 2595-2603, May 20, 1976.

(following is a very excellent article, but some of the logic is based on extrapolation and theory)
"Neutralization of Fossil Fuel CO2 by Marine Calcium Carbonate", Brodecker, WS, and Tagahashi, T., (sorry, I can't find the name of this review journal, I think its a collection called The Fate of Fossil Fuel CO2, tdw) Lamont-Doherty Geological Observatory and Queens College, pp 213-241.

"Effect of Pressure on Carbonic Acid, Boric Acid, and the pH in Seawater," Culbertson, C., and Pytkowicz, RM, Limnology and Oceanography, Vol 13, NO 3, pp 403-417, July, 1968.

(the following I included based on comments some have made about the effect of dust from the Sahara on climatology and reef pops in the Caribbean... ...CHRIS , BUT may be applicable more so than I originally thought.)
"Influences of High-and Low-Lattitude Processes on African Terrestrial Climate: Pleistocene Eolian Records From Equatorial Atlantic Ocean Drilling Program Site 663", deMenocal, Ruddiman, Pokras, Paleoceanography, Vol 8, NO 2, pp 209-242, April 1993.

"A Comparison of the Equilibrium Constants for the dissociation of Carbonic acid in Seawater," Dickson, AG, and Millero, Frank J, Deep-Sea Research, Vol 14, NO 10, pp1733-1743, 1987.

"Calcium Carbonater Preservation in the Ocean", Philosophical Transactions of the Royal Society of London, Series A, Mathematical and Physical Sciences, Vol 331, Issue 1616, The Deep Sea Bed: Its Physics, Chemistry, and Biology (Jun 19, 1990), pp. 29-40.

"Carbon Fluxes at the Sediment-Water Interface of the Deep-Sea: Calcium Carbonate Preservation," Emerson, Steven, and Bender, Michael, Journal of Marine Research, Vol 39, NO1, 1981. (note by tdw: very applicable to us in this discussion).

"Respiration and dissolution in the sediments of the western North Atlantic: Estimates From Models of in situ Microelectrode Measurements of Porewater Oxygen an pH," Hales, B., Emerson, S., and Archer, David, Deep-Sea Research, Vol 41, NO 4, pp. 695-719, 1994.

"Material Fluxes and Modes of Sedimentation in the Mesopelagic and Bathypelagic Zones," Honjo, Susumo, Journal of Marine Research, vol 138, NO 1, pp 53-97, 1981.

"Fine Scale Distributions of Porosity and Particulate Excess 210^Pb, organic carbon, and CaCO3 in Surface Sediments of the Deep Equatorial Pacific," Jahne, RA, Emerson, SR, Cochran, JK, and Hirshberg, DJ. Earth and Planetary Science Letters, Vol 77 (1986), pp59-69, 1986.
(Getting close with this one, interesting repercussions if their theories are right based on feeding activities of benthic organisms in field studies...)

"Dissolution of Calcite in the Deep Sea: Theoretical Prediction for the Case of Uniform Size Particles Settling Into a Well-Mixed Sediment," Keir, Robin, American Journal of Science, Vol 282, pp 193-236, March 1982.

"Measurements of the Apparent Dissociation Constants of Carbonic Acid in Seawater at Atmospheric Pressure." Mehrback, C, Culbertson, CH, Hawley, JE, and Pytkowicz, RM, Limnology and Oceanography, Vol 18, NO 6, pp. 897-907, Nov 1973.

(interesting but not directly related to the discussion)
"Influence of Productivity Variations on Long-term Atmospheric CO2," Mix, Alan C, Nature,, Vol 337, 9 Feb 89, pp. 541-544.

"Changes in Copper, Zinc, and Cadmium Concentrations in Anarctic Ice During the Past 40,000 Years,"Batfiol, Francious and Boutron, Claude, Nature, Vol 337, 9 Feb 89, pp 544-548.

"The Solubility of CaCO3 in Seawater at 2(degrees)C based upon in-situ Sampled Pore water Composition," Sayles, FL, Marine Chemistry, vol 9, pp 223-235.

(biggie)
Chemical Fluxes From a Sediment Trap Experiment in the Sargasso Sea," Spencer, DW, BRewer, PG, Fleer, A, Honjo, S.et.al., Journal of Marine Research, Vol 36, NO 1 (?), pp 493-523, 1978.

(good basic science review article on the chemistry and science behind the issue)
"Geolgical Perspectives on Carbon Dioxide and the Carbon Cycle," Sundquist, Eric T., US Geological Survey, Reston Va. circa 1982...

and finally:

"Particulate Fluxes of Carbonate and Organic Carbon in the Ocean. Is the Marine Biological Activity working as a sink of the Atmospheric Carbon?" Tsunogai, Shizuno, and Noriki, Shinichiro, Tellus Vol 43B, NO2, pp. 256-266, 1991.

I actually have quite a few more articles, but I have not read the rest of them yet, and I can't tell you yet if they are useful to the discussions. I have found much info, but no smoking gun in terms of the overall process.

Although I am sure that heavy metals play a role in the appearance of "Old Tank Syndrome", I am not convinced that it is the salt mixes, especially in systems that maintain regular water changes (more on this when I have finished reading the rest of the articles) and have at least SOME export mechanism for bacterial detritis and avoid supplementations with trace elements. Although I like the idea that Don P. has presented (the closed feeding within a system with true refugiums), a support refugium for a system would have to be huge for such a coral grocery store to be totally closed, although even a moderately sized refugium would help to limit the introduction of unnecessary outside potential toxins. In terms of Carbn, this system, even if adequately sized for a captive reef, would still be capable of fixing nitrogen and carbon from the atmosphere, and much like the Antarctic shelf, heqavy metals, etc still pervade our environment, requiring removal as Don has so eloquently pointed out (btw, Don, nice post! ) Foodstuffs will still be the major culprit in additions, but the DSB will be the final resting place for them in the long run. Floc and food and detritis removal will delay this, but prolly not stop the process.

Many many many variables come into play, and I am not so sure that those substances that bind with carbonates or are precipitated as carbonates/phosphates will be available in sustems that maintain high Ca and CO3 levels. Theoretically, once these substances become part of the substrate, so long as it is not disturbed and there are no large changes into the low pH arena, precipitated Ca and Carbonates will remain as part of the sediment bed or would be locked up/recycled as sandbed bacterial biomass (much the same way we can have near zero nitrates in the water column and a cyanobacterial bloom at the same time). This in actuality means that the sandbed will always become the end-sink with the highest affinity for heavy metals for closed systems, as the bacteria are certanly not going anywhere in a heaolthy system and will actively assimilate these substances into their biomass. This definately would make removing the sand bed every 4 or so years somewhat appealing to me, but I am not so sure that I would want to do this from the display tank (think remote sandbeds and detritis trap). As long as the Ca and Carbonate (alkalinity) levels are at saturation, so that the predominant equilibrium drives Ca into the sandbed as the solubility of Ca is exceeded, then there is little posibility of these DSB releasing the metals sinked there.

THAT is the trick though...
How do we assure that this will always be the case?

Hmmmm... the Dual Remote sandbed idea with a settling tank is sounding better and better... ...at least having the two sandbeds would give us the ability to change out one of the sandbeds on an alternating 2 to 3 year schedule without causing a major disruption to the main system.

More later. Still thinking much about the overall scenario.

This blows I already set up my tank. This hobby is beginning to not be fun anymore. When I think of the money I spent just for a syndrome to happen and I will lose everything. BLAH! Also this hobby is full of contradictions:

DSB - Yes or No
Water changes - Some do some don't
Additives - Harmfull, beneficial ?
Type or lighting best - Sorry we can't decide.
Salt mix best - Full of biased reports
Test kits dependable - Some work some don't
Best cleanup crew- Hermies , snails, crabs can't decide.
Metals - What the??? I'm not throwing nails into my DSB.
Refugiums- Good , oh wait until the algae goes sexual.
Water flow - 1 gph to 5,0000 gph

AND I HATE MY NEW MUSHROOMS THAT WILL NOT STAY ON ANY ROCK!

[Spanky]

>Also, would the LR we are putting in our closed systems already have a lot of end detritus in them from the places they were collected from?<

Yes and also as things in the LR die off, you stand a good chance of getting even more. Anything land based and mined will also contain land based organics and metals which will later be incorporated into these bacteria's matrix.

>Ok I would like a little more detail on how all detritus is not processed in a DSB. Maybe a link or 2 on a study even, <

It might be way too early for me to do this, but you guys can develop it from here.

Mike, it depends on your definition of detritus I guess. As long as it has nutritional value and there's something in the system that can utilize that nutrition, it will be run through again. Be it worms, cucumbers, pods, and then finally bacteria. Because bacteria can be so diverse and so plentiful, and because they will get to it first in any stage, and because they will get to it last too - they are the driving force. Even metals and organics that are initially locked up in CaCo3 for example are later freed up and re-cycled by bacteria.

>Oh yea and I would like to know what end product detritus is.<

It's that proverbial piece of shrimp and has been passed around so many times that there's no nutritional value left for anything in the system. At that point all of it's components have been broken down, complexed, or combined to the point that there is nothing in the system that can get anything out of it.

>So my questions stands what EXACTLY is being left behind and what does end product detritus consist of.<

Any metals, organics, carbons, etc etc that further processing is either limited by what they are, or limiting factors in that particular closed system (types of infauna, depth of sand bed, circulation, dominant species of bacteria, etc etc)

>Although I would presume that it's made up of whatever the fish had been chowing on...<

and not digested very well either. LOL

>First there is the area of how tightly do these substances adhere to Carbonate sediments? <

Not that tight when you allow bacteria to get at them.

I'm getting another cup of coffee and looking for Mike some links now.....

[Spanky]

biomineralization

http://cseg.ca/conferences/2000/247.PDF

http://www.udel.edu/PR/Messenger/93/2/24.html

nice read anyway

http://www.uft.uni-bremen.de/mm/engl/aboutus.htm

[aquaticsdeptleader]

freedom of thought stalonRon must be going nuts.

[SPC]

Originally posted by Spanky
It's that proverbial piece of shrimp and has been passed around so many times that there's no nutritional value left for anything in the system. At that point all of it's components have been broken down, complexed, or combined to the point that there is nothing in the system that can get anything out of it.

Any metals, organics, carbons, etc etc that further processing is either limited by what they are, or limiting factors in that particular closed system (types of infauna, depth of sand bed, circulation, dominant species of bacteria, etc etc)

....and so no matter what we do there will be a certain amount of detrius that must be manually removed from the tank, right? This build up can be prolonged by different factors, but will still occur, correct?
Now the question for me is, how are the animals effected by lower amounts of nutrients being added to the tank, (and I know there is no black and white answer to this either, many variables). If in Dons case his animals are finding plenty of nutrition through the already exsisiting natural foods in his tank, then I would presume this to be the best of both worlds. In my case however, I do not have an abundance of natural food in my tank unless I specifically concentrate on introducing nutrients to feed them.
Example; I have a 75 gallon sump/ref with about 50 lbs of L/R, a 16" x 12" - 6" DSB, many varieties of healthy macros and do not get an abudance of bugs unless I feed them directly. I can watch their numbers ebb and flow in direct relation to how much nutrition (in the form of dead protien) they receive. This being the case, it seems to me that I still need to add a certain amount of nutrients to the tank/ref in order to keep the animals in the system fed.
Steve

[Spanky]

>....and so no matter what we do there will be a certain amount of detrius that must be manually removed from the tank, right? This build up can be prolonged by different factors, but will still occur, correct?<

And that's the big benefit of DSB's. They make it a lot easier to people to set up these systems simply because they offer a larger margin of error. The fact that they will take care of a multitude of sins but they will not completely eliminate the inevitable. Just delay it.

>Now the question for me is, how are the animals effected by lower amounts of nutrients being added to the tank,<

Steve, I'm not sure I'm following your question/s here. I think maybe it would boil down to what you're specifically trying to feed. Most all of what's called 'soft' corals appreciate higher nutrients in the water column. Some other corals are able to farm their own bacteria and receive the nitrogen/carbon directly that way. If I'm following you correctly, it would really get down to the specific animal.

[SPC]

Originally posted by Spanky
Steve, I'm not sure I'm following your question/s here. I think maybe it would boil down to what you're specifically trying to feed. Most all of what's called 'soft' corals appreciate higher nutrients in the water column. Some other corals are able to farm their own bacteria and receive the nitrogen/carbon directly that way. If I'm following you correctly, it would really get down to the specific animal.

Well thats part of it Jerel .
Lets say that I am striving for, as close as I can come to, a closed ecosystem (as Don Is).
Don says:
"Nutrients in the SB and water column (detrituous) ======> algaes,planktonic life and micro/macro fauna ========> pods, critters and thier offspring ====> fish and corals ====> detritous ===> nutrients in the SB and water column"

With an average bio load in a reef tank, will this process be adequate to feed all of the animals in our tanks?
Lets say this tank is 180 gallons with a 75 gallon sump/ref and the skimmer is turned off. There is a 6" DSB in main tank along with a small 6"DSB in the ref. 120 lbs of L/R in the system. 440 watts of VHO over the sump/ref + 960 watts VHO over main tank.
The animals include:
2 banggai cardinals
2 percula clowns
3 papillose blennies
1 royal gramma
5 red leg hermits
100 various species of snails
5 mithrax sculptus
1 sally light foot
3 peppperment shrimp
15 different varieties of gorgs ( all photosynthetic)
10 SPS (5 different varieties procured on L/R)
1 flower anemone
40 ricordea polyps
30 seamat polyps

Now, IYO can I have a thriving reef tank by adding no nutrients in the form of proteins? How about if I only added protien once/week? Will there be enough of the pods, critters, algaes, planktonic life, micro/macro fauna constantly in my system to supply adequate nutrition for a thriving reef tank?
Hope this makes more sense , and I hope this appears to be on topic to others as it does to me.
Steve

[aquaticsdeptleader]

once long ago the milkway put an everest sized additive into the closed system known as earth effectivly changeing that closed system for ever considering the size of systmes relative to this scale i imagine this to be a good compartive example.

everything will always be in a constant flux of equilibrium till overload because of build up, what prevents this from happening on the reef (as the reef is an oasis in the desert thats where stuff builds up)? hurricanes storms ect, (blows stuff out into desert? (our case somewhere in new jersey)?

my blind rederick leads me stumbleing into Tom's "remote" (cant you hear Britney) rotational sandbed swap it out and live it up barry it with the flowers and hope for perinnial tullips idea (improvesied but genarly the same idea)



jim

[kestrel]

Wow this is facinating reading, and I've spent entirely too much of my work-day on it...

Let me see if I can help out some of the others reading this who may be having trouble understanding the build-up in the systems that is being discussed. (This should also help me make sure I'm understanding it.)

As Don was saying, he is striving for a fully closed eco-system. If it is truly a closed system, then everything gets recycled. Nothing new is added. Others are saying, "well I am only adding blender mush, and I try to remove the same amount through skimming, water changes, harvesting macroalgae, etc, etc." Part of the problem that is being alluded to, but not clearly stated, it seems, is the inclusion of persistent bioaccumulated toxins (PBTs), such as mercury and lead (Easy examples, but there are lots of metals, and organics that fall into this category).

Any time ANY food from outside the system is added to the "closed" system, very low levels of these PBTs are added to the system. (As an aside, if you don't think these things are there, go ask your doctor to run a full metals analysis on a sample of your blood. I was shocked the first time I had this done for work and had results with lead, and mercury, and... If you are over 35, the lead you see will be from leaded gasoline combustion in cars many years ago )

Back to our story - As other animals consume the food, their bodies store these PBTs (thus bioaccumulating). Then when that organism dies or is eaten by another, it returns ALL of the PBTs to the food chain, but this time in slightly higher levels than anything that the now-dead organism had consumed. Repeat. Repeat. Repeat...

Now you have PBTs working through the system at levels that are approaching toxic affects. Check the history of Peregrine falcons and ohter birds of prey and the use of DDT.

The reason the closed system that Don is advocating would be an improvement is that no PBTs would be added. Although it also stands to reason that as the PBTs move up the food chain, when a large organism (fish) dies (including all of its accumulated toxins) we remove it from the system, so that it doesn't create a "spike."

OK that's enough for me. Can someone else confirm that I'm on the right path?

I think I'll go home and do a water change and clean my DSB some...

Daryl

[cyberchef]

SPC your PM box is full, send me your email addy...

[Flatlander]

Acoustic, I have to agree with you. I said when some of this crap started, "the day I have to throw out several thousand dollars worth of live rock, is the day I put goldfish in my 225g tank".

Question Jerel. How come the success of some long term sandbed tanks? Where does the crap go in those? I assume every deep sandbed advocate does not agree with Rons deductions on replacement either.

After to many years in the hobby and to many different types of tank, filtration systems, I have the answer. "NOT".

Another question? If sandbeds are so good for ones tank, how come they stink so bad on removal, they make one regurgitate?

I think part of the answer is to either run a system like Cyberchief, with little fish popuation and little added foods or if like myself and most others whose fish would starve without multiple daily feedings;
Easy to clean tank, substrate, etc. and lots of filtration and flow. Besides my almost 6000gph flow, I run a large beckett skimmer direct from and back to the tank and a large ATS, direct from the tank also. I also run in a hang on power filter, quality carbon and at times Poly filters in the same.

My tank contains only rubble in front and only enough GeoMarine crushed coral, {large enough for siphon cleaning}, in the back to keep the leopard happy.

[SPC]

Sorry Don , I have my PM cleaned out now as well as showing my E mail.

Posted by kestrel:
Part of the problem that is being alluded to, but not clearly stated, it seems, is the inclusion of persistent bioaccumulated toxins (PBTs), such as mercury and lead (Easy examples, but there are lots of metals, and organics that fall into this category

-No doub't about it, it is a very big concern. The problem as I see it is can we run a thriving reef tank without adding some animal protien that contains some heavy metals. There is no question in my mind that what Don is doing is exactly the way I would like my system to run (please note my low animal load), but I know through my experience that my system is not self supporting at this time. I know that if I don't add some form of animal protien, then I don't get reproduction of the lower animals on the food chain that will support the other animals in my system. I sure wish it did, but its just not happened so far .
One thing I could do is grow these animals and algaes outside my system and then introduce them as needed. I wonder though, would the foods I need to feed these animals also contain heavy metals to some degree that was absorbed through my toxic salt mix? And when I introduced them to my system, how much organic material would I be adding in the form of dead or dying critters that might go uneaten? And....
Steve

[CAT]

I set up my tank so I could keep corals and fish. If a closed system requires the changing out of sand and rock down the road, I figure that that's the price I pay. Until that times comes, I feed my fish every day, do water changes every couple of weeks and enjoy the critters in my refugium.

I'm very glad that people are looking for a better way to keep reefs and I think many good ideas will come out of these debates, but I have to say that for myself, I never expected my tank set-up to last forever...Heck, my tank looks different every few months.