sponge bio filter

matgvr

New member
has anyone here ever experimented with a sponge colony used as a bio filter, What I'm reading about sponges it makes me think they may be able to out filter the usual filter methods, or at least add to the filtering process dramatically. Here is a good article ; Biologists have discovered how a reef-dwelling species of sponge can filter enormous amounts of carbon without growing in size.

The sponge Halisarca caerulea can absorb up to two-thirds of its own weight in carbon each day by shedding cells at a rapid rate, according to research by Jasper De Goeij at the Royal Netherlands Institute for Sea Research in Texel, the Netherlands, and his colleagues. In a study published in the Journal of Experimental Biology1, the team proposes that this fast turnover may be a tactic for coping with the toxins and pathogens that are frequently encountered by the filter-feeders in their environment.

H. caerulea is found on tropical reefs in the waters of the Caribbean, and feeds by filtering carbon-rich organic matter from the water. Earlier work by De Goeij had shown that the sponges could absorb prodigious amounts of carbon yet didn't seem to grow in size. "We calculated that a sponge should double in biomass every three days, but found that H. caerulea hardly grows at all," says De Goeij.

Absorbing science

To find out why, De Goeij and his colleagues collected growing sponges and stained them continuously with a chemical that labels actively dividing cells. The team cut samples from the sponge bodies at different time points up to 10 hours after the first exposure and analysed them for signs of the labelling agent.

They found that certain cells that pump and filter water in the sponge divided very quickly "” once every five hours or so1. But adding a second chemical to search for dead cells revealed only a few in the chambers, which left them with a puzzle: the sponge wasn't growing, but the cells didn't seem to be dying off.


Each day, H. caerulea absorbs up to two-thirds of its weight in carbon.E. van Bommel
De Goeij was stumped until he gave a presentation on the sponge's impressive cell division to a group of cancer researchers. They immediately recognized the rapid division behaviour as being very similar to that of the human gastrointestinal tract. Cells in the epithelium of the colon are replaced every 12"“24 hours by rapid proliferation and then shedding. "Once we looked at the sponge tissue with the human colon in mind, we found massive amounts of shedding," says De Goeij.

Other marine biologists are surprised by the find. "Nobody has looked at cell sloughing in sponges like this before," says Malcolm Hill, a marine ecologist who specializes in sponge evolution at the University of Richmond in Virginia.

Filter-feeding frenzy

De Goeij and his colleagues suggest that the rapid growth and shedding of the cells may be an evolutionary response to the harsh conditions in which H. caerulea grows. To survive in the nutrient-sparse Caribbean Sea, the sponge must filter vast quantities of water, which is likely to increase its exposure to toxins and pathogens. Rapid shedding might prevent such problematic materials from building up and damaging the filtering system, Presenting his results to the Maastricht Pathology Department, someone said "˜Lets look at this like a human intestine, then you should see shedding where old cells detach from the epithelia'. De Goeij knew that he had seen some loose cells, and thought that they were artefacts from cutting the samples, but when he and his Pathology Department colleagues went back and looked at the samples, De Goeij realised that choanocytes were shedding all over the place. And then De Goeij remembered the tiny piles of brown material he found next to the sponges in the aquarium every morning. I was Thinking of building a sponge filter box [simplified Picture below] so i can incorporate them into my sump. the box would be 24'' x 16'' x 16'' tall and hold 143 14'' acrylic rods to anchor the sponges to. Im not sure if beneficial bacteria can live on and in a sponge or not,But if it can The potential for a super biological filter is very good. Example ; a cubic foot of sand has 8000sqft of surface area for bacteria to live on. And One Tethya sponge the size of a quarter has 4500 sqft of surface area, so a cubic foot of these small filter feeders would yield over 2,007,000 sqft of surface area for [ potentially] bacteria to grow on. Sponges can consume 50% to 75
% of there body weight in organic carbon and other reef wastes ever day. In the picture/diagram below you can see the slide out tray.This would be for collecting the detris and brown discarded cells shedded from the sponge in order to export wastes from the system.If you ever have noticed the little piles of brown detris under your rocks and considered it to be general wastes ,you may be just seeing brown cells from your rocks sponges.
 
If I understand your design correctly it's basically a cryptic zone where the bottom can be slided out for cleaning. The acrylic rods seems too complicated to me, a grid of simple white egg crate would work just as well.

In stead of the slidable bottom you could consider putting some flow across the bottom (small pump/spraybar), this will collect the brown cells you describe nicely which you can either simply siphon out or if flow is strong enough will circulate through your system and will eventually be caught by mechanical filtration like a filter sock.

Cryptic zones do work. I have two large cryptic zones in false walls in my 2200 liter tank (using egg crate grids for surface area). I would post a picture but the insides are completely covered with sponges, worms and small turnicates :-)

My tank is 120 cm deep (about 47") and on the left and right sides I have a fake wall (made out of black acrylic) giving me a 7" wide, 47" long and 26" high chamber on each side. The fake wall has slots near the bottom and my tunze streamers (4 on each side) are positioned near the top. On the bottom of the chambers, about an inch beneath the input slots is a 5" sandbed, on top of this a grid of egg crate ending an inch below the powerheads. This creates a flow from bottom to top through these chambers (and nicely hides the big ugly Tunze's). Any brown cells will simply be blown in the tank and will end up in my mechanical filtration. Originally I did this simply to hide the dual overflows (in the back corner of these chambers but later on added the sand beds and egg crate grids to utilize the tank space lost and reading about the value of cryptic zones.

It takes a very long time for the area to be fully colonized by worms, sponges and turnicates (my tank was setup in 09) but I believe it to be worth it.

Marc.
 
interesting mark ,the egg crates a good cheap way to anchor the sponges. The acrylic bars that i have in the picture where going to be about 14'' long and welded to the top piece of acrylic and hang down in the dark/cryptic zone inside the box, The egg crate grid will serve as a much better anchor medium.Im curious how your water quality is? and have you tried bumping up your feeding regimen slowly/daily to see what your system can handle ? Id really like to keep my detris/cells confined to one area somehow,so i don't need to purchase bigger mechanical filters /protien skimmer ext.
 
Ouch, answering that is a long story, where to begin.....

My tank was set up in 09 and since then I experimented a lot with it. Stocking has been very low (both corals and fish) and basically I never fully started it up (technically it was finished just the stocking was left to do). I started feeding the tank while it contained only life rock a few weeks in and gradually increased feeding. I wanted to find out how much the filtration could take and after the initial cycle i never measured any nitrates and phosphate. At the height of my feeding experiment I dosed liquid food from a small fridge 24/7 (about 20/30 cubes of frozen food a day! while I only had about 20 small fish in there) basically i was feeding the microfauna and those fed the fish. Pod populations were insane.

Note that I also ran 2 pretty big ATS's and a ATB super cone skimmer and a 100 gallon fuge with assorted macro's. It seemed that the tank could handle just about anything I threw in, no detectable nitrates. How much of this was due to the cryptic zones is hard to say, too many variables to draw a proper conclusion. Judging by the growth of sponges and other life inside those area's I would have to guess that they definitely helped, if not for nitrate reduction then for sure for bio-diversity and life food production.

I had to shut down the feeding from the fridge after a leak developed inside the fridge and destroyed my dosing pump and magnetic stirrers (and the fridge)(should have connected the output of the dosing pumps to the feed line using a venturi). That and some health issues made me lose interest in the tank. I have to admit I basically neglected maintenance (filling up the top off reservoir was basically it). I'm ashamed to say that I hardly fed the fishes (sometimes weeks between feedings) but strangely everything simply kept running and the fishes were healthy and fat.

There were some other incidents that affected the tank, when I was still running 1600 watt HQI and 600 watts T5 the ventilation of the fish room failed and as a result the tank peaked at 31 degrees (88F). Last fall I switched to LED and because the tank used be heated by the HQI's i never bothered to install heaters.... Last winter it was pretty cold outside (-20C = -4F) and the fish room (being an extension to my house) cooled to 12C (53F). Tank bottomed at 17C (62F). Due to health issues I wasn't paying much attention so both periods lasted who knows how long. Nearly all inhabitants survived.

Lately my health is improving and with that my interest in finally finishing the tank. About two years of lack of maintenance is no fun to clean up (scraping 2 years worth of coraline of about 33 square feet of black acrylic for example (side and back walls)) but the tank is starting to look decent again. I also fixed all the issues that went wrong (like the heating) and installed failsafes/alarms on anything that might go wrong. That the tank didn't crash even with all the abuse I've put it through can (IMHO) be at least party contributed to the sponges and worms in the cryptic areas.

Even with all that my water quality is excellent, NO3 0.50 ppm, PO4 0.04 ppm, KH 7.7 Ca 450, Mg 1280, pH 8.2. No GFO, no carbon, no vodka or pellets just algae, good skimmer and cryptic zones.

So to sum up my tank and all it went through is not a good model for the working of cryptic zones. I do believe however that it played a huge part in keeping things relatively stable even with all the abuse.

Marc
 
hey marc thanks for getting back to me, first off I'm glad your health is getting better and you have found your interest in your tank with it. And thanks for the ideas on the sponge box they will save me money and work a lot more efficiently. Seeming my tank is on the newer side and lightly stocked , I should be able to see what my tank can handle before and after the sponge filter is added to a degree. There will always be variants I'm not seeing and accounting for ,but generally I should be able to see a difference . And of coarse il need to find out away to grow/collect/ and propagate sponges as quickly as possible.
 
Matgvr,

Basically all you need to do to create a cryptic zone is to provide a dark area with lots of surface area for the sponges, turnicates and worms to grow on. They will come by themselves and in my experience there is no need to seed and or put in sponges yourself.

Be sure to read the monster thread about cryptic zones (duplex sump thread http://www.reefcentral.com/forums/showthread.php?t=969713) lots of interesting info in there.

Marc
 
While I am a fan of sponges and grow lot's of them, even dosing silicate for them, I think the filtration aspects are somewhat unclear.

Suppose that you are correct that they shed cells representing a large fraction of consumed organics, what do you suppose happens to them?
 
Is your question ?,what happens to the cells that have dropped off? If so According to the article above the cells are shedding and drop off.So in a closed environment like the aquarium they would be shedding back into the system and breaking down releasing there waste back into the water, unless caught and removed from the system. I have no idea if sponges will work as a super filter or not.I just keep reading published studies online focused on the sponges vast ability to consume large amounts of carbons and nitrates. I do appreciate your knowledge, and your calculator by the way. Im by no means an expert in any field regarding aquariums ,but i do love to experiment and try to improve .
 
Much of the same in this article but the water purification part at the end is interesting "It seems that 90% of a cave sponge's diet consists of dissolved organic carbon. Previously, it was believed sponges mainly fed on particles".

De Goeij discovered that these cave sponges play an important role in the food cycle of the coral reef. Algae and corals produce a great deal of organic material. Because a great deal of this is dissolved in the water and is very difficult to break down, very few organisms can use it as food. If nobody uses this food, it will wash out of the reef and into the ocean. Energy would leak out of the system. De Goeij, however, has proved that much of the dissolved organic material is taken up by the cave sponges. He was able to determine this by measuring the amounts of carbon, nitrogen and phosphor – the basic elements of all life on earth – that went into the caves and how much came out again. It seems that 90% of a cave sponge's diet consists of dissolved organic carbon (DOC); previously, it was believed sponges mainly fed on particles.
Intestines

But what exactly do the sponges do with all that food? They can’t invest in growth because the space is limited on a coral reef. De Goeij discovered that they mainly use the food to rejuvenate their cells. ‘Sponge cells divide incredibly fast. By comparison, cell division in a mouse’s intestine takes at least half a day. Sponges take between 5 and 6 hours. According to De Goeij, sponges need to do this because they come into contact with so much dirt. ‘Sponges filter their food out of the water. Because they live in a nutrient-poor environment, they sometimes have to pump 100 liters of water a day. This increases the chances of a sponge coming into contact with all kinds of viruses, bacteria and poisonous substances. These things can cause permanent damage. In order to avoid this, the sponge constantly rejuvenates its cells.’ Remarkably, the structures the sponges use to take up their food are very similar to the human intestinal tract. ‘Sponges are about 700 million years old and are our oldest multicellular ancestors. It looks like our digestive tract has not changed so much during evolution.’



Sponge cultivation

Thus cave sponges constantly produce a huge stream of dead cells which – unlike the dissolved organic material – can be easily eaten by the other organisms on the reef.

Figure 3: By using a flow cell, the uptake and usage of dissolved carbon by the sponge can be determined (photograph: Dr. Jasper de Goeij).

Has De Goeij’s research resolved the Darwin Paradox? ‘No, it hasn’t. But at least we now understand better how such an ecosystem can function – by recycling efficiently.’ He hopes that his results can be used in sponge cultivation. ‘That’s not really successful at the moment. Perhaps we’ll get better at it now we know exactly what they eat and how cells grow and die.’

Tiny medicine factories

De Goeij sees a lot of applications for cultivated sponges. Because they are outstanding filters, they could be used to purify water. But sponges also contain substances that could be used as medication. ‘Sponges are tiny chemical factories, but the substances they produce are so complicated that it is much too expensive to synthesize them and the medicines would be unaffordable. It is therefore important to develop good cultivation methods for sponges. At the moment, natural medicines mainly come from plants and animals that live on dry land. However, 70% of the earth is under water and the sea contains a wealth of interesting substances.’

Curriculum vitae

Jasper de Goeij (1977) graduated as a biologist in 2001 at Wageningen University. In 2003 he started his PhD research at the Royal Netherlands Institute for Sea Research. His supervisor was Prof. G.J. Herndl of the University of Groningen. The research was financed by NWO. His thesis is entitled Element cycling on tropical coral reefs: The cryptic carbon shunt revealed. He and Dr Ronald Osinga will be continuing research with their own company Porifarma (www.porifarma.com).

"De Goeij sees a lot of applications for cultivated sponges. Because they are outstanding filters, they could be used to purify water. Sponges also contain substances that could be used as medication."

References:
 
I have a 100G Rubbermaid that I turned into a cryptic fuge. It is fed by one of my overflow drains from the display (probably gets 700 - 800 gph).

I ran a overflow pipe along the bottom with holes drilled on the sides so that the water circulates from the bottom up through the rock and out along the top. Next I placed fine aragonite sand on the bottom so that POM could be processed naturally by bacteria/copepods. I have a spacer of concrete bricks then placed plastic privacy fence as a support for the rock. Next I filled it up with about 25% LR and the balance DIY rock using rock salt (rock soaked for 6+ months before using).

Tank has been running for around 3 years. I probably have around 6 or more different types of sponges. While certain sponges will self colonize, I try to add diversity by adding new sponges from other reefers tank every chance I get. I would like to see more sponges in the tank after this amount of time, so if you have a chance to seed it with sponges it would be a good idea.

If you have the room, I believe that this is a great idea. Presently I feel that my tank benefits more from the amount of rock than the sponges. Granted I only see the top layer of rock, so the bottom may have more sponges, and I'm aware of it.

I'll try to post some pics, but presently at work (can't here) and probably will not be able to until after the weekend.
 
Is your question ?,what happens to the cells that have dropped off? If so According to the article above the cells are shedding and drop off.So in a closed environment like the aquarium they would be shedding back into the system and breaking down releasing there waste back into the water, unless caught and removed from the system. I have no idea if sponges will work as a super filter or not.I just keep reading published studies online focused on the sponges vast ability to consume large amounts of carbons and nitrates.

I'm just questioning that process as a plus, which you seemed to be touting. I'd rather they grew than shed their cells back into the environment, where they will die or something else will have to eat them (or maybe some get skimmed).

In other words, consuming a lot of stuff isn't all that useful if it just gets relesed again. Much of what they eat may be bacteria. Exchanging bacterial cells for sponge cells isn't necessarily a big filtration plus, IMO.

That said, I do like them, they do obviously grow, and I do think they may be useful to decrease bacteria in the water. That's perhaps part of why many of us who dose organic carbon (vinegar in my case) see lots more sponge growth when dosing compared to before we did so. They may also consume it directly, or the bacteria inside of them do. :)
 
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