Freshwater Deep Sand Bed (DSB)

[XanAvaloni]

There was a thread here a few weeks ago in which someone described a way to get riccia to carpet. You get some of the mesh cloth used for cross-stitch work and cut 2 pieces to the size and shape you want. Then evenly distribute the riccia evenly over one piece, attach the top piece and loosely stitch them together. Toss in tank to float or stick to bottom with rocks. After awhile--I think the time period was a week or 2 but can't swear to it--you take the top piece off and the riccia stays attached to the other one.

As best I remember it anyway. Search for "riccia" and it ought to turn up here. Because you're right, otherwise it will float away. It is both so tiny and so lacking in roots to be very difficult to persuade to stay in a substrate.

 

[DeeDeeK]

Those theorists have now become part of the hobbies fairey tales and are held up as gospel. Really happy you are both proving them wrond

When you get the spreadsheet sorted I'd like to have a look at it

My DSB will be 6-7" deep so will need to grade substrate, found out today that MTS only graze the top 2" of the substrate and marine DSB's have a 50% sand change every year

The rest odf the post's I'll go over tomorrow as it's hard to type on this netbook

I'll certainly share my spreadsheet. I'll make it editable in "Excel" (no, not the liquid carbon supplement!) so anyone else can make a correction, addition, or revision. This'll take a while since I'm teaching myself how to use "Numbers," my spreadsheet application (an Apple application that's compatible with "Excel") as I go.

Ah, those good ol' theorizers and they're supporters, the ones who repeat and distort the original unvalidated theory. Have you read/heard about how malayan trumpet snails will turn over the sand and break up and prevent pockets of anaerobic decay? I love that one. I guess we're supposed to think the snails just hold their breath while the traverse the low and no oxygen zones at their agonizing "snail's pace" as they mix up the hazardous pockets.

I've never seen an mts go deeper than about one inch, but they do it to get down to the really juicy, predigested mulm and bacteria that accumulates
in the sand so if they're finding it a 7/8 inches down, the wouldn't likely go deeper. Nope, they don't solve the "problem" of anaerobic sand. They probably just reassure their misinformed fishkeepers enough that she or he leaves the sand alone, as it should be left.

Anoxia: What a lovely sculpture! I love the lines of movement and the contrasting shape/motions of the tail, back, and neck with the more angular limbs. I actually haven't practiced my art for a long time now but I actually am/was a sculptor too! I used clay, usually high-fired, to build sculptures and the occasional sculptural but functional piece like sushi trays. I just love big, thick, blocky slabs and cubes!

I think of aquarium keeping as an art, just as bonsai or landscaping for examples are. To me, the beauty of an aquarium lies in the richness and complexity of the biological system within and the art lies in our participation in the process - the aquarium is an ongoing process, you see - of the aquarium's being through simple tools. In a way, approached from the right direction with a certain state of mind, it shares a bit in common with Japanese tea ceremony: When one begins their session of aquarium keeping or contemplation, one enters another emotional state and to truly participate with rather than simply manipulate and control the aquarium one must become present and open to their senses, the practice of their technique, and the needs of the miniature ecosystem. It can be a form of meditation and if you feel the wonder and love of the life nurture through this practice, a spiritual act.

I look at my aquarium, at the plants, fish, and invertebrates with my eyes. I look INTO the aquarium & residents thereof with test kits, a thermometer, my understanding of the various processes at work, and correlating my visual observations. I enjoy just seeing the aquarium and its merry residents but I love the beauty of glorious, complex life as it is embodied in that little biological system and I feel somehow nurtured by the very act of nurturing these delightful, little communities.

A hypothethesis which I strongly believe to be true: In human evolution, there was a turning point, no doubt, when our ancient ancestors began to affiliate with wild dogs. People who affiliated with dogs benefitted from their protection and assistance at home and while hunting while the dogs benefitted from our much better skills at planning and organizing, using tools, and tendency to love little puppies and take good care of them - and dogs tend to do the same for their "master's" little kids. I'm sure that our advanced primate-skills of identifying with and understanding the inner state of others is what allowed us to dig what dogs were doing and feeling so that we could co-operate. More successful dog-affiliates were better communicator/empathizers and passed their genes down as did dogs which were better able to identify human emotional expression and communication - we domesticated dogs but dogs domesticated humans! Human social interaction and language was synergistically boosted to the next magnitude of complexity as was our capacity for reason. AND, people who liked other critters benefitted from their affiliation and the trend toward identifying with and the impulse to nurture them evolved and grew stronger and more subtle.

This was the start of the human trait of identifying with, coming to know, and coming to participate consciously and with purpose in the living systems around us. We also use these skills to interact, bond, and nurture one another with human social/familial systems. So, we are instinctively oriented toward identifying with, participating with, and nurturing life in general just as we are oriented that way to other people. Nurturing and feeling love are things must healthy people experience in caring for babies. OR puppies. OR just about any living thing we become attached to. Even a dopey little fish which takes headers over the side of its tank down to the carpet.

The arts involve the deeper levels of human emotion, awareness, cognition, and at least a touch of spirituality. When those things aren't involved, a thing or activity no matter how pleasing and stimulating is a craft. Nothing wrong with craft at all, though. Just, well, art needs to be recognized as SOMETHING special. Maybe we need a new adjective or noun or verb to go with it.

The practice of aquarium or fish keeping can be a hobby, a pastime, a craft, a way of having a conversation piece of just a bit of kinetic "art"(a different use of the word "art" is just to label a decorative object, as we all know). Or, it can be an enriching activity raised to an art and/or a spiritual practice, with its roots in some of the most fundamental instincts and emotions which make us human. It can enrich the aquarium-artist and it can enrich the aquarium admirer/contemplator.

I say let's throw away ALL the epoxy-coated, unnaturally colored gravel, decorative air-bubblers, stop breeding those awful deformed fish call "ballon," like ballon mollies, balloon blue rams, etc. and let's get those people with those really big, spartan, show-off tanks - like 200 gallons and stocked with a huge arrowana, freshwater stingrays, huge oscars, maybe a piranha, and some other big flashy aggressive fish (the kind of fish which a real man's man keeps)(no offense, men. I exaggerate to make a point and it's easier to paint the picture of a stereotype and knock it down than to be realistic sometimes [just listen to politicians on the campaign trail as they topple straw man after straw man]) to donate them to public aquariums or simply to cook and eat the fish. Poor things, swimming around in a completely unstimulating environment, over crowded, and stressed out constantly. Check out youTube and you can find video footage of such travesties proudly displayed by folks I feel very sorry for, with their missing out on the more subtle and healthy parts of life as they are drawn to flash and smoke, stimulating but beyond that not very interesting practices, and complete lack of aesthetic sense. Crowding together a bunch of large, predatory fish driven by an appreciation of power, viciousness, sleekness, size, and being exotic in an ugly little rectangular body of water with glass walls is the opposite of art, spirit, beauty, nurturing, and all the deep and warm emotions.

Once I was talking with a very spiritual fellow. I turned to dark, ironic, dismal humor and he stopped speaking with me without a word and went back to his work the clay studio we shared (with like 25 other people). The next day I tried to apologize and he said he hadn't been offended. He turned away because, he said, everything which comes into us through our senses and into our minds in some way alters our minds and brains just as everything we eat alters our bodies in some small way. Like nutritious food nudges our body in the direction of good health when we eat it and junk food the opposite. You see, our experiences cause emotional reactions in the brain and the brain is always rewiring itself and alters the balance of neurotransmitters in response the these stimuli. Also, we remember, which means an impression of the experience is held now in the brain, and it can feed back on itself and reinforce behaviors or diseased states of being. If the brain didn't change, we wouldn't be able to really remember.

So, this guy asks me would I prefer to sit down to a well balanced meal or I prefer to sit down to a plate of dogsh?*t! Well, not to make a rude comparison like my very spiritual friend did me, I'll say I'd rather sit down in front of a fascinating and varied living system with plants and substrate, and healthy relaxed and not over crowed fish which are themselves varied such that they're a just a few of the "cool" fish in a barebones aquarium but they have the "cool" factor by being predators and there. I don't know. To each their own, and to each the consequences of getting there own, ad infinitum down the generations. I don't know much but I am sure that many people are locked in spiritual states where the aesthetic and the spiritual are carried away by flash and heat and they really miss out on some important things. I'm grateful, for one, to benefit from the slow pace of the freshwater DSB aquarium and the life within, which allows me time to grow seriously more in tune with the aquariums I keep aesthetically, emotionally, and spiritually. I am so against just landscaping and planting a tank all at once; we should introduce plants and then proliferate them slowly to fill in the tank as the bed grows more fertile

I've been up since 2:20 AM and now it's 5:30 AM and suddenly I'm so tired I'm having dizzy spells. So I'll conclude this without a conclusion. Think of this entry as being an ode to the art and nature of the aquarium.

I can't help it, this has been another crazy rant. Spirituality, evolution, aesthetics, biology, communications - what am I missing now? I keep falling asleep while typing, mid-sentence! I'm going to bed.

 

[anorth_uk]

Problem is those with big tanks and one or two fish in are recreating real life closer than we are cramming large amouns of fish into a small water column, it is very rare to find large amounts of life in a small volume in nature. There's a restaurant in Bangkok that has about a dozen arrowana in an 8' high tank, would love to have that in my house - although it's a bit of a waste as they only use the top 16" or so of the aquarium.

Spent my day trying to resue my fry tank, 21 down to 6 fry, for some reason got a case of the dreaded white spot, so the nursery tank recycling in the kitchen will be going to waste soon, but gives me more time to get the sump DSB started, hopefully will get the wier made and installed this week, then just need to source the sump pump.

MTS are very common in cichlid tanks as they do keep the substrate sorted , and prevent pockets of anaerobic decay but we only tend to have a couple of inches of substrate

Apparently they only change half the sandbed in a marine DSB per year, not sure why as I wasn't really interested enough to read all the thread.

Found a resource for UK inveribrates so will be checking those out to see which will survive tropical tank conditions and raid mom's garden pond, thinking of a few handfuls of the mud at the bottom to kick start my DSB, then graded sand on top going to gravel for the top half inch or so

 

[Anoxia]

It worked! Overnight was the true test of whether I had enough agitation. I checked on the fish first thing this morning, half expecting them to be gasping at the top, but they were perfectly happy, not even breathing a little bit fast. Third time was the charm. Thanks for all the help DeeDeeK, I know I'm kind of a slow learner with all this, but you have been very patient about teaching me.

I agree that aquarium keeping, and art, and spirituality can all go together. I sometimes think of The Creator as the ultimate master Artist, Who uses Nature, (light, wind, water, and living plants and animals) as materials, instead of just paint or whatever, like human artists do. We artists don't have the power to give life to our works of art, no matter how talented we are, but we can still work with living things, and one way is through keeping creatures in natural habitats like aquariums and terrariums.

We are kind of godlike in our creating a habitat, sustaining in it all the complicated processes of Nature, and being the source of everything the plants and creatures inside it need to live happy and healthy lives. We can even sort of participate in creating life too, through propagating the plants and animals we keep. One could say the world is basically God's really gorgeous and incredible terrarium, and humans are his favorite pets. Just looking at all the infinite wonders of nature, you can see what a good terrarium keeper the great Artist is, LOL.

 

[DeeDeeK]

Problem is those with big tanks and one or two fish in are recreating real life closer than we are cramming large amouns of fish into a small water column, it is very rare to find large amounts of life in a small volume in nature. There's a restaurant in Bangkok that has about a dozen arrowana in an 8' high tank, would love to have that in my house - although it's a bit of a waste as they only use the top 16" or so of the aquarium.

Spent my day trying to resue my fry tank, 21 down to 6 fry, for some reason got a case of the dreaded white spot, so the nursery tank recycling in the kitchen will be going to waste soon, but gives me more time to get the sump DSB started, hopefully will get the wier made and installed this week, then just need to source the sump pump.

MTS are very common in cichlid tanks as they do keep the substrate sorted , and prevent pockets of anaerobic decay but we only tend to have a couple of inches of substrate

Apparently they only change half the sandbed in a marine DSB per year, not sure why as I wasn't really interested enough to read all the thread.

Found a resource for UK inveribrates so will be checking those out to see which will survive tropical tank conditions and raid mom's garden pond, thinking of a few handfuls of the mud at the bottom to kick start my DSB, then graded sand on top going to gravel for the top half inch or so

Hmmm. yes. MTS keeping the entire approx. 2 inch depth of a bed of sand turned over regularly actually would help prevent anaerobic pockets. I've been thinking in terms of MTSs trying to plow through already established pockets at depth, where the MTS would quickly suffocate. It hadn't occurred to me that they might be in a sand bed the depths of which they could plumb so that the entire bed remained one, single, aerobic region. I'm quite sure that with a sand which resists compaction and has good, relatively large interstices would remain aerobic on its own much of the way down, would allow H2S to diffuse upwards faster than it could accumulate, and since it's aerobic would be relatively deep, between aerobic H2S eating bacteria and the simple tendency of H2S and O2 to react readily together in solution to form HSO4 (not H2SO4!) and H2O no H2S would reach the water column (where what little of it remained from the original quantity down below would react with O2 rapidly and be rendered harmless before it could harm anything). A deep sand bed with really good sand and a not ridiculous amount of organic matter and sulfates entering it will destroy H2S before it causes harm even without plants and invertebrates helping! The central principle powering a good DSB is the entry, formation and most especially movement (diffusion, infiltration) of minerals, organics, and dissolved gasses and provide scads of surface area internally to house the bacterial communities which perform most of the magic. So, movement of stuff, bacteria, and depth (to provide space for the aerobic, anaerobic, and anoxic zones to form and time for the "stuff" which enters the bed to be sufficiently processed. That's all it really is. The multicellular organisms serve to boost the capacity for diffusion and infiltration and to serve as or groom and enhance habitat for aerobic bacteria. Given a smallish load and good sand, the sand and bacteria don't need any of us multicellulars.

Myself, I don't strive to recreate natural habitats or necessarily imitate or idealize their appearance. I strive to create an attractive, interesting, relatively stable system which tends toward good water, good plant growth, and healthy, active animals sometimes in higher numbers than conventional stocking guidelines would suggest, oh, and little algae. By juxtaposing the right natural elements together with the right, least intrusive possible bits of artifice, I can assemble and participate in a little, nature-like community which will settle into the kind of system I've already described - not teetering toward one kind of disaster or another, depending on careful control of numerous artificial elements to stay healthy and attractive. The aesthetic lies not simply in color, placement, and of kinetic parts (fish and inverts and sometimes amphibians) of a composition but in easy balance of so much glorious life and our natural human instincts to embrace and nurture bits of the natural world.

I detest the whole overcrowded "cool," for the most part predatory - piscivorous fish with big gulping mouths, fangs, or simple size and aggression. Such aquatic menageries are gauche, cruel, and show off nothing of the aquarist's skills as such, rather they show their ignorance or heartlessness toward the fishes' well being and comfort and their ability to spend money on large, expensive fish and large, expensive tanks and canister filters. It's sorta like owning a muscle car which rarely or never gets to travel at maximum speed or perform the extreme sorts of maneuvers it was ostensibly built for but the driver is unlikely to have the skill or derring do to execute or tacky, expensive jewelry - it really only demonstrates questionable taste and an interest in displays of power and status. Really, this is quite unimpressive.

Another thing I detest is the flowerhorn craze. First of all, they actually are ugly and though their coloration and pattern are ornate and can capture the eye's attention, their shape is awkward and unnatural, the actual colors are bland and ugly and so what, they're just another expensive status symbol in my opinion.

OK, I'm an aesthete and a bit snobby at times. But I am NOT an elitist.

 

[Anoxia]

Here's a quote from a saltwater forum, about deep sand beds:

"Many people have an exaggerated sense of how much "sifting" should occur in a deep sand bed.

The kind of sifting you guys are describing would actually reduce the effectiveness of the setup.

Deep sand beds are supposed to be stagnant, that's the whole point.

Only the very surface needs to be sifted, and only in a very minor way. In fact, that sifting is mostly for the benefit of the saltwater tank's surface organisms, so if you aren't going to have those in a freshwater version, it becomes even less imperative.

The kind of sifting some people have started assuming a saltwater DSB needs is actually enough to be harmful to the process. For example, sand sifting stars are bad for a deep sand bed. It can function with them, but the SSS is actually sifting out the smaller organisms that are good for the bed, while it does nothing beneficial, itself.

Likewise, the people who advocate stirring a small segment of the bed regularly, in order to keep the bottom from building up toxins, are completely failing to understand the concept. That, too, does nothing but undermine the whole purpose of a DSB."

I think that you don't want or need as much denitrification in Freshwater as you do in salt, but if you have plants, their roots prevent the substrate from going too dangerously overboard anyways. The person to whom this quote belongs has put into words something I was thinking. If Anoxia is the cause of denitrification (well, anoxic bacteria) than you want as little oxygen as possible in the lower part of the substrate. Having lots of big interstices between particles is great for the top of the substrate where the aerobic bacteria live, but at the bottom, where anoxic denitrification occurs, wouldn't you want the finest particles? It seems to me that's how it should be, but I could be wrong.

 

[Anoxia]

I ordered Diane Walstad's book, it should arrive this week. Yay! I have also been researching clay, specifically the denitrifying capabilities of clay. When you google "clay denitrification" you get lots of scientific results, and I've been learning tons. My mom is a groundwater hydrologist, so she has been explaining the terms to me.

I've found quite a bit of evidence that clay is a better denitrifier than sand. It appears you want about 60% clay for optimum denitrification, and it helps if there are organics in it to keep the anaerobic bacteria going. I feel better about the organics I left in the bottom of my aquarium now, but though some is good, I just have too much. I think I will still use topsoil, but not mulm, other than the mulm that eventually accumulates on it's own.

I also read that 75% of the denitrification tends to occur in the first 3 or 4 inches of soil, so I think I won't go over 4 inches in the future either. My current DSB is 4.5 inches. Anyways, I just wanted to get those little facts written down before I forget them. I was going to do quotes and links, but tonight is movie night. Those who are that interested can just google "clay denitrification" like I did.

 

[DeeDeeK]

Here's a quote from a saltwater forum, about deep sand beds:

"Many people have an exaggerated sense of how much "sifting" should occur in a deep sand bed.

The kind of sifting you guys are describing would actually reduce the effectiveness of the setup.

Deep sand beds are supposed to be stagnant, that's the whole point.

Only the very surface needs to be sifted, and only in a very minor way. In fact, that sifting is mostly for the benefit of the saltwater tank's surface organisms, so if you aren't going to have those in a freshwater version, it becomes even less imperative.

The kind of sifting some people have started assuming a saltwater DSB needs is actually enough to be harmful to the process. For example, sand sifting stars are bad for a deep sand bed. It can function with them, but the SSS is actually sifting out the smaller organisms that are good for the bed, while it does nothing beneficial, itself.

Likewise, the people who advocate stirring a small segment of the bed regularly, in order to keep the bottom from building up toxins, are completely failing to understand the concept. That, too, does nothing but undermine the whole purpose of a DSB."

I think that you don't want or need as much denitrification in Freshwater as you do in salt, but if you have plants, their roots prevent the substrate from going too dangerously overboard anyways. The person to whom this quote belongs has put into words something I was thinking. If Anoxia is the cause of denitrification (well, anoxic bacteria) than you want as little oxygen as possible in the lower part of the substrate. Having lots of big interstices between particles is great for the top of the substrate where the aerobic bacteria live, but at the bottom, where anoxic denitrification occurs, wouldn't you want the finest particles? It seems to me that's how it should be, but I could be wrong.

Anoxia, I think YOU ARE the cause of denitrification in the world!:thumbsup:

I agree about interstices. With larger interstices, one needs a deeper bed, probably in a geometric ratio to those interstices, to develop anaerobic and anoxic environs. I like largish interstices because solids can infiltrate more rapidly, and there is a deeper aerobic layer where nitrification happens (and actually, denitrification takes place in anaerobic zones within the biofilm even when that biofilm is in an aerobic region! In soil this the general case). As the organic detritus sinks into the DSB and is eaten by bacteria, oxygen is consumed. The more detritus, the more O2. I've observed in my larger freshwater DSB that since I've moved the messier fish/bigger eaters out and replaced them with little rasboras and celestial pearl danios, the regions of black and grey sand have retreated downwards and faded out almost altogether and my nitrate levels have been 20+ppm rather than ~10 ppm. It's just a correlation but I suspect my bed's anaerobic capacity has shrunk, therefore less denitrification and greater nitrate. My plants have also slowed down and become a bit more fragile. My guess is there are less CO2 and minerals being liberated in the bed.

Perhaps a downside to such an open sand bed is that it can not only handle a large bioload but perhaps needs one to really get cooking. However, a super-fine substrate won't really absorb mulm that quickly, which is probably why the mixture of 60% clay is recommended to contain organic matter to feed the anaerobes, so it may be able to remove loads of nitrate, nitrite, and ammonia, and probably hydrogen sulfide too but it may not serve as well as a "filter" of solids or a rooting medium. But then, this might all depend on how totally soggy and saturated the clay is, since it can exist in almost any state, from a haze in the water to a hard, leathery solid with slippery outsides, in water.

I've pondered using a two-tiered sand bed, with this very large grained stuff my LFS owner foisted on me recently, on top of the pool filter sand he sold me for like 10x markup before I realized what I was buying. (Grumble. Good thing for him he has good advice and excellent fishes!) which is much finer. Perhaps this idea calls for the pool filter sand on top of a mixture of clay,some pond muck, sand, dolomite, and peat. Then the mulm could be taken in and have a nice place to rot out of sight and there'd be a nice big aerobic zone as well as an anaerobic/anoxic clay level.

There's so much to be learned! mud, clay, sand, silt, soil!

As regards sifting the sand, I heartily agree. I like worms who help O2 down a ways because it deepens the aerobic region and feeds a tad of O2 to the lightly anaerobic region where much denitrification takes place and holds the sulfate-reducers at bay (they live only in the heavily anaerobic (anoxic)regions). MTS are great because they also keep the aerobic region a bit deeper (I believe) and churn mulm into the sand as they move along.

The idea that sand must be stirred is just so embedded in aquarium-lore, it's frustrating.

 

[DeeDeeK]

I also read that 75% of the denitrification tends to occur in the first 3 or 4 inches of soil, so I think I won't go over 4 inches in the future either. My current DSB is 4.5 inches. Anyways, I just wanted to get those little facts written down before I forget them. I was going to do quotes and links, but tonight is movie night. Those who are that interested can just google "clay denitrification" like I did.

I must point out that soil above water is terribly different from soil, sand, or clay underwater. My understanding is that denitrification occurs within the biofilm surrounding grains of soil, within above-water soil. I think Walstad mentions this.

I have no idea what that means for DSBs.

Oh, you'll love your Walstad book! I just know it!

Gosh it'd be swell to do some side-by-side comparisons of otherwise identical tanks with substrate-beds of different compositions, layered and un-layered.

 

[Anoxia]

That is interesting, I'm glad you shared that experience about moving the heavier feeding fish, and losing some denitrification. I agree that a layered bed is ideal, too. Looser on top, denser underneath. That's now it is in nature. One of the things I read also said that denitrification ramps up to a high level once the really fine particles reach 37% in the substrate, so I'm going to use that as the minimum in my tanks.

I agree, a lot of the research on denitrification that I turned up either had to do with wastewater treatment (my mom's field of specialty) or agricultural soil. I don't have a great mind for science, like you do, so I just have to track down whatever random pages I can on the subject, and try to suck as many facts out of them as possible. As always, if I contradict anything you know to be true, DeeDeeK, (or anybody else) please correct me!