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RE: DSB article - CALFO

charlesr1958 — Thu, 08 Nov 2007 17:03:05 GMT

Anthony - Gawd I hope not! But doubt it since you would think it would come up out of the sand at night, which I've never seen. All of these unknowns is exactly why I want to get some out to Dr. Ron. Big set back on that front, but am working on getting around it. I might have to get a business license and take advantage of FedEx's business to business shipping waiver on marine life. I also find it frustrating that even with the vast amount of information available now, I still get told by others "my lfs said that a dsb will crash and kill everything in my tank". I shouldn't be too surprised though since I have at least ten reasons for why Ich is so persistent in aquariums, which range from it coming in through the use of tap water to it having developed the ability to fly or drift about as a pollen spore would.

Nicole - Would have loved to have found those myself as with them being but a few inches, I think they would have made for a better choice than the foot long synaptids I get.

Chuck

RE: DSB article - CALFO

NicoleC — Thu, 08 Nov 2007 14:27:50 GMT

[quote]charlesr1958 (11/8/2007)

Hi Nicole,

I would have loved to have seen that species. Any chance you could get one from whom you sold the tank to? Do you know where the live sand came from?

Chuck[/quote]

No, no chance. I don't have any contact info for this person, and I'm 2500 miles away now.

I had sand and rock from MANY sources, retail, wholesale and hobby level. I was a good little DSB keeper and nabbed useful critters whenever I could find them. Due to the size of the little cukes, I have to think they may have come in as larvae or attached to a rock or coral. It seems unlikely they could have survived the live sand collection and shipping process as adults; they would have gotten squished.

Here's a photo:

RE: DSB article - CALFO

Anthony Calfo — Thu, 08 Nov 2007 09:36:12 GMT

wow... great stuff! I cant help but see a likeness in the first image to the famous Tiger tail Holothurid of the Pacific (Holothuria hilla). They are superb and efficient sand "cleaners" but they eventually grow to be a meter long! Yet most on the reefs seen are only a few inches long to a foot or so. It crossed my mind that maybe your Holothurid is a baby hilla-monster (pardon the pun ) and you've found the nursery part of the reef for them :p

RE: DSB article - CALFO

charlesr1958 — Thu, 08 Nov 2007 06:15:47 GMT

Hi Nicole,

I would have loved to have seen that species. Any chance you could get one from whom you sold the tank to? Do you know where the live sand came from?

Chuck

RE: DSB article - CALFO

NicoleC — Thu, 08 Nov 2007 05:33:21 GMT

I had a few hitchhiker denizens of an apparently similar species, some sort of cucumber. They were not harmful at all and probably quite beneficial. Mine, however never exceeded 1" in length and I don't believe they worked at more than an inch deep. While yours may be more beneficial in some ways, mine may be more viable in aquaria since they would require less food. They hung around for years (and since I sold the tank with sand bed intact, may still be alive) and may have reproduced, since the odds of getting several of the same hitchhiker seem low.

I think something along these lines would be great to see available from some of the critter sources, like Inland Aquatics.

RE: DSB article - CALFO

charlesr1958 — Thu, 08 Nov 2007 05:18:07 GMT

Hi Anthony,

I have, what I believe is the cure for what ails a great many deep sand beds. As you mentioned, such sandbeds gained a bad reputation just out of ignorance (not knowing) sandbed biology and/or how to properly set one up to begin with. The two biggest issues facing us hobbyists is in keeping the sand infauna thriving and having enough water flow to force the "food" down into the sand to where the sand infauna can deal with it.

Being that it is highly likely that the sand infauna includes both predators and prey species, I would imagine that over time, the predators could devastate their prey. Basicaly eating themselves out of house and home. That and being able to restock such sand infauna is not always an easy option or having the patience to wait for a seeded bed to reach its former glory, regardless of why the life was lost.

A little over a year ago, While on a hunt for sand dwelling polychaetes, I uncovered both a sand dwelling synaptid and a sea cucumber species, I say sea cucumber simply because it has not been described to the best of my knowledge, nor has the synaptid. Both species are found in the same sand, (composition and grain size) that we use within our own systems, and at a depth that is reasonably recreated (6 inches on average). Wanting to increase my tank's diversity, and just being curious, I add three of the synaptids to my dsb and was pleasantly surprised to see them actively injesting the sand (at depth). At the time, I did not think to try the sea cucumber as I had assumed it was only using the sand as a daytime hiding place. Over time, I noticed that I never encountered this species anywhere but down in the sand. So I took one home and added it as well. It never once surfaced and once up against the glass, it was easy to see it also injesting the sand grains just as its surface dwelling cousins do.

To keep all things "fresh" within my dsb, I was in the habit of siphoning out 1/5th of the sandbed every two months in an attempt to keep the sand infauna thriving as well as getting rid of excess organics. Having added the above mentioned critters, I have not touched my sandbed in over a year now. Last week, I had a large, powerfull powerhead lose its suction on the glass and it pointed straight into my sandbed and blew that area right down to the glass bottom. While it made a sandstorm or course, I was quite thrilled to see that once the pump was turned off, the sand quickly settled out of the water and not a trace of the "dirty, muck" one normaly expects to see deep down in a sandbed. The entire sandbed from top to bottom is kept constantly cleaned and moved about by the synaptids and sea cucumber.

I honestly believe that these two species will pretty much idiot proof a dsb, or at the least, remove a lot of the maintenance or worry of having a dsb. Hopefully silencing the critics once and for all while making a reef aquarium, that little bit more of actualy being a reef.

I am at this time, trying my best to get some live specimens out to Dr. Shimek for his study as I can only go by my simple observations. If the good Dr. does give them his seal of approval, I then hope to be able to make these species available to the hobby, if not myself, then at least I can try and talk the exporters into carrying them should a demand be generated.

I have also been collecting these species and sending them to fellow hobbyists here in the Philippines.

http://www.reefphilippines.com/forums/viewtopic.php?t=4687 They went like the proverbial hotcakes...lol

And for those with high speed access, A 2mb movie of a synaptid in action

Chuck

RE: DSB article - CALFO

Anthony Calfo — Thu, 08 Nov 2007 01:34:56 GMT

yes... both used but separated is more appealing to me. Most aquaria simply do not have enough water flow or nutrient export mechanisms to pull off mixed grain and (especially) coarse grain beds.

As for the silica sand... without seeing (do ask) for a chemical assay of the product (they have it... they have to), I would not take the risk. As easy as it would be to send you an assay copy... there is a reason if they don't

RE: DSB article - CALFO

PCIALF — Wed, 31 Oct 2007 15:22:29 GMT

Anthony Calfo (10/29/2007)

I have not... but I'm curious to know your perspective on why it might be good? I can see theoretical merit either way. If used, the silica would have to be screened off to be kept above (prevented from being tilled into the oolitic and very fluid aragonite).

The article made me think about the 2 different benefits in size and wondered if a combo separated as you said would have any benefits

RE: DSB article - CALFO

Hawk — Tue, 30 Oct 2007 09:27:33 GMT

Hawk (10/26/2007)

Hi, My tank is 375g, 500g total water volume. I plan on installing a rdsb in a 40g Brute garbage can. I'm debating on sand choice. If I were to use a mix of aragonite and play sand would it be better to mix the two together or put one layer on top of the other? Also I currently have a ssb (.5"-1") bed of larger 3-4mm aragonite I plan on getting rid of. Can I use this to kick start the rdsb or is it's size going to be counter-productive?. I also have an extra 30lb bag of the larger (3-4mm) aragonite in storage can it be mixed within the (guessing 500lbs.) of smaller sand? Thank-you.

Hi Anthony, any thoughts on layering different sand versus mixing them together? I'm having a tough time time in finding out the make-up of the play sand I can get locally. The supplier tells me that it has been flame sanitized, silica free and is pulverized igneous rock from a quarry on Vancouver Island, but that is about it. I'm usually pretty cautious about my tank but to go all aragonite I'll be looking at well over $1000 with shipping vs. less than $100 for play sand. Without knowing the exact make-up of the sand do you feel this is a major risk> Thanks

RE: DSB article - CALFO

Anthony Calfo — Mon, 29 Oct 2007 22:01:17 GMT

RE: DSB article - CALFO

PCIALF — Sat, 27 Oct 2007 14:42:39 GMT

Great Article Anthony

I am using Aragonite in MY RDSB but after reading this article on the thoughts of the different media have you thought or tested a RDSB with Aragonite and maybe a few inches of silica sand on top

RE: DSB article - CALFO

Hawk — Fri, 26 Oct 2007 08:52:15 GMT

RE: DSB article - CALFO

Anthony Calfo — Mon, 05 Feb 2007 17:15:32 GMT

What little experimentation/research has been done into the issue of performance of sand at depth seems to indicate that even shallow beds can denitrify as well as deeper beds. The caveat being that shallow beds inherently have less "real estate" (read: less potential) for larger biotic faculties in time (or as bioload/needs increase). Thats why I prefer and recommend deeper beds (4-6" minimum maintained).

RE: DSB article - CALFO

ToddLaCo — Mon, 05 Feb 2007 12:24:45 GMT

Anthony,

I have just plumbed two 40 gallon tubs into my home display. One is going to be a 10" deep RDSB using Pavestone, Pulverized Limestone (I know the buffering isn't quite as good but it seems to work for me), and the other will be a dedicated refugium which I would like to put the Seachem, Gray Coast in.

Since the Gray Coast is being used mainly for it's buffering abilities and not necessarily a DSB, is it important to have a certain depth? The tubs are only about 15" deep and the Gray Coast tub is primarily a refugium, so I don't want to use too much of my depth on sand. I am hoping for the Gray Coast to be about 3" max.

Thanks

RE: DSB article - CALFO

Anthony Calfo — Mon, 05 Feb 2007 08:04:22 GMT

Thank you my friends... its just really an overview pitched as a mass market article for some overseas friends (magazine). Stilll I hope/believe it is helpful

For depth in sand... less than 3" can work, but more than 4" is better IMO for display DSBs. And, as you may have seen already, the RDSB buckets are much deeper.

Carl... I do very much recommend you adding the live rock ASAP to the display and letting it develop without fishes or corals as long as possible. For seeding, the "kits" are generally poor values and low biodiversity. You will get far greater mileage out of buying a recently transhipped piece of "red algae/kelp rock" from Indonesia or the like. Fresh live rock will have far more worms, bugs and other goodies to seed your mature live rock. For feeding the live rock and critters... its tough to say. But likely just a weekly pinch of algae and meat based fish foods will be of some benefit and no harm. Lets see what develops in the rock after the first month before we address what to feed them.

BTW... adding live phyto weekly while curing the LR and LS will be a huge help for spurring beautiful sponges and other cool filter feeders in the absence of harsh grazing fishes and crabs/shrimps.

RE: DSB article - CALFO

MattTVI — Mon, 05 Feb 2007 06:10:56 GMT

For anyone who's interested, in Anthony's favorite links section, there is a DSB article hosted on WWM that talks alot about depths!

RE: DSB article - CALFO

MattTVI — Mon, 05 Feb 2007 05:50:11 GMT

Anthony,

Great article, thanks! I have kept a DSB (display) and aside from cycling, I have always had undetectable nitrate levels. I have also always been careful about what I add to the tank. This usually entails asking Dr. Ron what effect a fish I'm thinking about will have on the infauna. Suffice to say, I have resisted the urge to add many a fish on account of the negative impact it would've had on the sand bed.

I read the article and then scanded it again, did you mention a depth range? I didn't see one. I have heard a minimum 2.5-3" for a DSB to begin to work, but I have always targeted a range of 5-6" in my display.

thanks for the great read,

Matt

RE: DSB article - CALFO

Reefski — Sun, 04 Feb 2007 20:30:25 GMT

thank you for your thoughtful article. this is a topic that greatly interests me.

this makes me wonder. i am getting close to setting up a new 700 gallon tank + 300 gallon sump/refusium. i have been planning to have a DSB in the tank as well as in the sump/refusium.

i also plan to set the tank up and let it run for 6-10 months while we finish building the house around it. it will only be lit by the skylight shaft above the tank. i will not be able to set up the refusium/sump until after the house is completed. it will just have a temp small sump while the house is being completed.

how about a bit of live rock in the tank too? i have some nice mature LR in my present system complete with many sponges, tunicates, and other filter feeders.

i was thinking of buying some of the LS kits of critters, or just taking some of the sand from my current RDSB that has many fan worms and bristle worms, et al.

what should i be adding for food for the infauna while maturing for many months?

oh, i am also thinking about going skimmerless. my current tank with a RDSB has an Aqua-C skimmer that hasn't produced much since my RDSB got going a few months ago.

DSB article - CALFO

Anthony Calfo — Sun, 04 Feb 2007 18:27:58 GMT

DSB - Deep Sand Bed Potential

Anthony Calfo

For many years, we have seen the use of substrates in marine aquaria wax and wane in popularity. The issue has run the gamut from bare bottom through shallow bed to deep sand, and then back to bare bottom again. But even with the acceptance of truly deep sand beds in America by the mid 1990’s, DSBs did not see regular use until refugia were established some years later. The reasons are obvious, perhaps: refugia are smaller, more affordable and less risky “models” of deep substrates, which the average hobbyist can attempt with greater confidence. But even with fears aside, the addition of a deep sand bed to a full display (versus a small refugium) is an investment in labor and money. It is no wonder that the large-scale DSBs took some time to be accepted.

As the popularity of DSBs grew, the number of critics did too. Sadly, many of the most outspoken detractors argued in theory without even trying a DSB! And the majority of the rest of the critics seemed to unfairly blame their aquarium failures on their very limited DSB experiences. The more likely cause of their failures was from typical bio-overloads, poor water flow, and neglect of water quality.

The reality of successful DSP applications, however, is amazingly simple, albeit strict. For perspective, I can tell you that my experience with living substrates is not insignificant. I utilized 48,000 lbs (over 20,000 kg!) of fine sand for my coral farming greenhouse operation and have installed similar deep sand beds in over one hundred private aquariums for over ten years. In this article, I will share with you a very practical survey of the potential - and the limitations - of a deep sand bed application.

If I had to reduce the summary of challenges of deep sand bed applications to a single statement, I would have to say that new hobbyists have unrealistic expectations for what a deep sand bed can do. That is not to say that a deep sand bed does not have great potential! They truly do. But many people seem to have extremely high expectations for new sand to become teeming with life almost overnight in aquaria. Such a thing is difficult and requires careful orchestration, time and patience to happen. But more often, it fails because of impatience; aquarists stock DSB aquariums too quickly with predatory fishes that consume the foundling populations of desirable worms, microcrustaceans and other sand fauna, before the sand life can adequately populate to sustain predation. That is an enormous mistake. The inferior biotic faculties struggle to process the all-too-common overload of fishes, food and waste in aquaria, and the DSB fails in such circumstances.

A similar problem occurs in DSB systems with inadequate water movement that allows too much particulate waste to sink and accumulate excessively in the DSB over time, causing the aquarium to “crash.” Instead, we should aspire (in bare bottom and DSB aquaria alike!) to always keep reef-like water movement with strong flow that keeps solid matter in suspension longer for greater feeding opportunities by the filter feeders and better processing by skimmers and other filters. Strong water movement in the aquarium is the number one key to success with long-term healthy DSBs. I recommend “sps-style” water flow of near 40-60 X turnover of the tank display for best results.

I can remember in the early days of reef-keeping in America, we would hear stories of great German aquarists that would keep their new live rock (for “Berlin” style systems) in the dark for six months or more with good water flow and supplementation (organic and inorganic). The purpose was to dramatically improve the quality of “cured” live rock with greater coralline algae and more life forms before lights and fishes were applied. Few American aquarists had the patience to do this at the time, but I think we must have admired the German stony coral displays so much and remembered the lesson that we apply it now to our refugia and DSBs. Now, with thanks and respect, we remind our European friends of this same patient advice: avoid adding predatory fishes or corals to DSB systems for many months to allow adequate populations of infauna to develop.

You will notice that these two fundamental pieces of advice are different from what most retailers and so-called experts will recommend. Both mistakenly tell you to add “clean up” organisms from the very beginning (note: at least one of those two people profit from this bad advice ). But the addition of predatory snails such as Whelk (Buccinid), Murex (Muricid), Mud (Nassarid) and Tulip (Fasciolariid) can be devastating to the desirable life forms in the sand of an aquarium. The popular Conch species (Strombids) are even worse as most will starve to death not long after they have decimated the infauna of a DSB. Of similar concern is the use of Holothurid “Sea cucumbers” (and Sand-dollars) and all of the sand-sifting gobies. These vigorous sifters destroy a lot of biomass in the substrate. Worst of all perhaps are the alleged “reef-safe” hermit crabs; these crabs are brutally indiscriminate predators on desirable sand bed life forms. The only thing that any of these aforementioned “bad” DSB organisms are actually good for is tilling the sand surface to prevent the buildup of brown diatom algae. But you can use a number of safer organisms to accomplish algae control without destroying DSB biodiversity!

Best bets for DSBs include: Stomatella-type “paper shell” snails, Ceriths (Cerithium and close kin) and most all errantiate polychate worms. Yes… “bristleworms” are very good. They are rate-limited in population by available food, which in turn is rate-limited by good water flow that prevents excessive solid matter from settling and accumulating over time (back to rule #1 above regarding adequate water flow). In time, you may even allow small Asterina-type sea stars to flourish (this is somewhat controversial, but they are generally harmless, if not helpful). For starfish, Ophiuroid species (Brittle or Serpent starfish) are perhaps best of all for being low burden, low maintenance and high utility as scavengers. After a year of establishment, various ornamental shrimps, such as Lysmata, may also be added; their benefit (producing larvae as food for corals) may balance with their burden (preying on DSB fauna). And for fishes, perhaps the best “clean up” group is the bristle-tooth tangs of the genus Ctenochaetus with their specialized mouthparts that comb diatom algae from the soft sand with little burden otherwise on desirable sand fauna. Manual sand stirring by the aquarist, though, is not needed when adequate water flow and livestock are in place. That said, manual stirring can be helpful for feeding some specialized filter feeders or extending the life of the sand bed when water flow is not ideal in support.

In time, you will see various colored algae appear to grow substratum, but they are only existing in tiny films between the aquarium glass and the sand face; they are not growing throughout the sand bed. Such algae are often stimulated to grow in front because of the indirect room light and the aquarium lights reflected down through the vertical panes of the aquarium. Many aquarists with adequate water flow and good DSB maintenance have also noticed that while moving an established sand bed, the overall substrate is remarkably clean and odor free like the first day it was placed into the aquarium! This is exactly how a healthy DSB should be after many years. I personally moved a nine-year old sand bed (15 cm deep in a 1000 liter aquarium that held two small reef sharks) that made this very same impression on me: clean, odorless, healthy living sand.

Perhaps the most underrated but also the most reliable and significant benefit to a DSB is the ability to reduce nitrates naturally and quickly. Over ten years ago I wrote about hobbyists using a remote DSB (AKA – “RDSB”) as a means of addressing the fears that many folks had at the time (and some still do) about “what if” a display DSB gets polluted or goes bad. It is true too; illuminated DSBs are more of a challenge to keep healthy because of the site competition (sand surface) between desirable and undesirable life forms with the increased availability of energy sources (food, waste, light). Yet, most all of the benefits of a DSB can be had with an unlit DSB reservoir that is plumbed inline to the main system. The typical RDSB application for home-sized aquariums (under 800 liters) is a large bucket full of sand (maybe 25 kg of fine sand in a 20 liter bucket) that has a supply of filtered water on a continuing path in the aquarium system. Some folks simplify it even further by sitting their RDSB bucket in an unlit sump and gravity feed water from a display or refugium above… or even a tee off of the sump pump manifold. The sump RDSB can then gently spill over the sides of the bucket into the open reservoir. It is quite simple and effective for mainataining nitrates below 10 ppm.

However you choose to install an inline (R)DSB, you can estimate that approximately 25 kg of fine sand (< 2mm grain size) per 400 liters of aquarium water will fully, or nearly so, reduce nitrates in a typical bioload. For over a decade, aquarists at large have reported struggles to keep nitrate levels under 40ppm with large and frequent water changes and other drastic measures to no avail. But, after the installation of an RDSB, nitrates were reduced in less than 4 months with many showing significant progress in 8 weeks or less. I have even observed several retail stores with heavy bioloads in central filtration systems see their nitrates reduced to near zero with the installation of a sand-filled 200 liter RDSB aquarium (1mm sand grain size… full nearly to the top with only 10 cm of water flowing across the sand surface). This is effective on 4000 liter fish holding systems! The single greatest benefit of a DSB is nitrate control. While many aquarists like to claim through the years that higher nitrates are tolerated by many fishes, the reality is that many other fishes do not tolerate it well. Reports about Pterois, Sharks and other predators, for example, implicate high nitrate levels as inhibitory to iodine uptake, which can lead then to thyroid hyperplasia (“goiter” in the throat). The condition worsens in time to the point where the animal is unable to feed.

Using the bucket RDSB as an example (versus refugium substrates or display DSBs), this is perhaps an illustration of all of the best and worst of a DSB application:

There is little risk and little gain (aside from great nitrate control) to healthy DSBs
Strong water flow above a DSB will easily keep it healthy, poor water flow will quickly destroy it
Anywhere you choose to install a DSB is simple and inexpensive, but laborious and cumbersome (space-consuming)
Living sand is like living rock: great patience produces superb quality living substrates, but impatience (stocking with fishes/corals too soon) produces worthless living substrates

One of the great advantages to having your DSB remote in refugia or a bucket is that it can be turned offline or bypassed rather easily if special needs call for it. Medicating the main display can be difficult or practically impossible with an in-tank deep substrate that absorbs medication and kills off a massive amount of infauana. But a remote DSB can run fallow on a small loop of recirculating water while the needs of the display are addressed in cases of emergency. If the RDSB fails for any reason likewise, its removal from the system can be a simple valve turn away versus an enormous project of draining a tank for display DSBs. My recommendation is most always to keep your DSB remotely for these reasons and more.

We must also consider the composition of sand used for DSB to support desirable life forms in and above the substrate as well as be supported by applied water flow. The “rules” for DSB sand are not very strict, but they are rather practical. When our stated goals are culturing low-oxygen faculties for nitrate reduction plus the minimal penetration of and accumulation of solids in the substrate over time, smaller sand grains are better suited for the purpose. I recommend sand grains under 2 mm in size for DSBs. Media that is larger than 2 mm can be used, but deeper beds and stronger water flow will be required to make it work successfully. Large sand grains allow excessive solid matter to penetrate deeper and faster and can lead to the problem that critics cite with DSBs becoming “nutrient sinks.” That said, a mix of large and fine grain sizes together can work if there is enough fine sand (< 2 mm) to fill the interstices. It is arguably better to mix DSB sands for greater biodiversity of infauna whereas a uniform grain size favors the dominant growth of certain organisms over others.

Lastly, there has been a bit too much debate, in my opinion, over the intrinsic composition of DSB sands. The three principal choices are calcite, silica or aragonite. Each media type has its fans and critics alike. All, I assure you, can be quite similarly useful without nearly the difference in performance that the critics would lead you to believe. The fundamental thing to search for with any of them is grain size as per above, without much concern for chemical makeup. The advantages and disadvantages of each class of sand are as follows:

Calcite DSB

advantages: commonly available, moderately priced, wide range of grain sizes

disadvantages: very little buffering ability over 7.6 pH

Silica DSB

advantages: very inexpensive from industrial sources

disadvantages: no buffering, limited sizes (<1 mm), poor shapes (sharp and lacking fluidity)

Aragonite DSB

advantage: optimal shapes (oolitic and very fluid), excellent buffering pH, and mineral supplying

disadvantage: generally more expensive and less available than silica or calcite

Depending on aquarists’ budgets and access to choices among sand substrates, each composition listed above can be used and finessed appropriately. The oolitic (round/spheres) shape of aragonite affords the most fluid DSB that naturally churns and feeds lower zones while reducing diatom growth at the surface. Silica sand, on the contrary, locks its sharp grains and packs with very little movement. As such, solid waste is less likely to penetrate, for better and for worse (less food for biotic faculties), while diatoms can grow more easily at the surface. A silica DSB will be less expensive to install but more expensive (labor) to maintain… perhaps requiring manual sand stirring and greater water flow. Aquarium hobbyists usually find calcite sand beds to be the best choice for aesthetics, price, availability and required husbandry; all are moderate.

With this primer, I hope to have provided you with a “noiseless” summary of the legitimate and practical expectations for what a DSB can – and cannot – do. If you can resist the extreme ends of the argument, I think you will find that this is a viable and reliable methodology for marine aquariums. With kind regards, Anthony Calfo