Flow Through DSB

[bioload]

Hi all,

I've recently started a new tank that is about 6 weeks old. This is a brief summary of the tank to date:

Volume - 75gal
Rock - 20lbs live 30lbs dry
Substrate - None
Livestock - 2 Clowns, a Tang and a pair of Coral Banded Shrimp
Filtration - Marineland Emperor 400 BioWheel Filter
Water changes - None to date

The tank has been through it's initial ammonia and nitrite rise and fall with nitrate now being my primary focus, which I would like to be able to control and better understand before I start adding any corals to the tank.

I looked near and far for information regarding Natural Nitrate reduction......... just when you thought you had enough information on the nitrogen cycle.

The Aquarium Nitrogen Cycle

What is the Nitrogen Cycle

Nitrosomonas

Nitrosomonas

Nitrifying Bacteria Facts

Nitrobacter

What does a Bio filter and a Denitrification filter do?

Anaerobic Respiration

Anaerobic wastewater treatment reviewed

Advanced Wastewater Treatment

Wastewater Management Fact Sheet - Denitrifying Filters

Denitrification - Advanced Wastewater Treatment Plant

Denitrification

Denitrification Filter

Wastewater Treatment with Methanol Denitrification

Deep Bed Denitrification Filters Play Role in Improved Wastewater Quality

Investigation into Methanol as a Carbon Source for Denitrification

Vodka Dosing...Distilled!

Aqua Medic Nitrate reductor

Nitrates in Marine Aquarium Systems

FAQs on Marine Water Quality involving Nitrates

Biological Filtration

Nutrient Control and Export: Ways to Increase Water Quality and Eliminate Nuisance Algae in Marine Aquaria

An Introduction to Deep Sand Beds

Hourly and Daily Variation of Sediment Redox Potential in Tidal Wetlands Sediment

Effect of Alternate Aerobic and Anaerobic Conditions on Redox Potential

The Food of Reefs, Part 6: Particulate Organic Matter

ORP and the Reef Aquarium

Hydrogen Sulfide and the Reef Aquarium

DSB in a bucket for nitrate control

In my search to gain a better understanding of the process, I thought this may be a good opportunity to look at nitrate specifically and it's removal since my tank is in it's early stages. The articles above raised as many questions for me as they answered.

That said, I would like to set up a remote deep sand bed and monitor/document specifically its effect on nitrate in my system. Based on what I've read results have been mixed.....surprised? My nitrate reading currently are 80-100 API test kit (any recommendations on test kits/monitors would be appreciated as well).

The first thing I would like to know is how long would it generally take for NNR to occur in live rock, so that any observed reduction can be attributed directly to the RDSB. If I were to add a RDSB right now, and I noticed a reduction in nitrates, would it be safe to assume that the reduction was due to the addition of the DSB, or was it some other process that was happening within the rock that I was not aware of.

Secondly, and more important, I would like to know how the flow within a DSB would effect NNR. Has anyone done any trials using a flow through RDSB, or any studies regarding the flow.

Any feedback on the subject would also be great. Hope to have the RDSB in place soon and interested in seeing what happens.

P.S. links are always appreicated (and always read......eventually).

 

[ruprecht]

The first thing I would like to know is how long would it generally take for NNR to occur in live rock...

If I were to add a RDSB right now, and I noticed a reduction in nitrates, would it be safe to assume that the reduction was due to the addition of the DSB, or was it some other process that was happening within the rock that I was not aware of.

Secondly, and more important, I would like to know how the flow within a DSB would effect NNR. Has anyone done any trials using a flow through RDSB, or any studies regarding the flow.

If there is a good coat coralline algae on the rock there may be enough bacteria in the rock. I have no hard evidence for this other than mature rock will have bacteria inside, but when it becomes mature is undetermined.

Adding and seeing RDSB effects right now would depend on the sand and if it was sterile or seeded. Bacteria grow fast, but patience and time are the two important things when establishing a functional RDSB.

Flow is the most important thing when designing a RDSB. A study has experimented with flow of 10cm/s 10cm above the substrate with surprising results.

This thread has some discussion of these things.

 

[bradhass87]

Another thing you could try is a fluidized sand bed. I know I know, just one more thing to spend another month reading about.

 

[wayne in norway]

There is a gobload of work on flow thro' sandbeds. I cna't advise better than to look at Professor Markus Huettels research groups work. SOmewhere on their homepage are some movies of modelled flow via a process called advection.

On the other hand (and bear in mind my work involves understanding fluid flow in rocks) I haven't a clue how denitrafication in live rock is supposed to get the nitrate in and the nitrogen out at anything beyond pitiful rates. There are lots of physical parameters making this a terrible proposition/theory. There are far better models using thick (relatively speaking) biofilms on the rock surface that are aerobic at the surface and have an anaerobic layer a few microns in, and these have been observed, measured.

 

[bioload]

Where to start?......I guess the first question that I have is, does a deep sand bed remove nitrates. I've seen many applications of sand which include substrates within the display tank, partitioned in a refugium, and even contained remotely in a bucket. However, I've only seen anecdotal evidence of its effects in an aquarium. Below is a DSB that I'm currently setting up in order to measure specifically the effect a DSB would have on nitrate in my tank.

Let me know if there are any changes that I should make or things to consider regarding this approach. Other system details have been listed above and will not change.

 

[Allmost]

a couple of notes :

1. your bio wheels are increasing you no3 by the second !! not a good filteration at all !

"I've seen many applications of sand which include substrates within the display tank, partitioned in a refugium, and even contained remotely in a bucket. However, I've only seen anecdotal evidence of its effects in an aquarium."
what have you tested ? how long was the DSB working for ? what were the readings ? I got zero readings fro n and p using remote DSB in fuge and in the reef tank itself if you have read the articles you posted, you would know

and lastly,your diagram is NOT DSB !!! that is fluidized sand bed
you are pushing water through it !!! I think you do not understand the Idea of a DSB the whole point of having 6" is to create an area with low Oxygen levels ! you are pushing oxygen throuhg.

that will only collect detritus on top, make them rot adn increase your no3 over time.

 

[TheFishMan65]

+1 the DSB I have read about have water flowing over not through.

 

[bioload]

+1 the DSB I have read about have water flowing over not through. - There will be little to no flow to start (drops/sec). I'm hoping the ORP meter will give me some information on the conditions once the flow is increased.

 

[bioload]

your bio wheels are increasing you no3 by the second !! - Which I'm hoping will be a steady "food" source for the DSB.

what have you tested ? how long was the DSB working for ? what were the readings ? - Thats what this thread is for.

I got zero readings fro n and p using remote DSB - in addition to......Euro reef skimmer, 10G refugium with 2 T5HO lighting and cheato., full out Zeo system,.....and don't forget the liverock. I'm trying to isloate (as much as I can) the DSB part.

if you have read the articles you posted, you would know
Now there's no need for that......Must be something in the water in the GTA

 

[Allmost]

hhaah bioload, dont get me wrong man

y tank info is after I switched to Zeo, I Was posting about before, only reason I switched to Zeo was cause of my seahorse tank added

anyways, back to the topic : pushing even drops per sec throuhg DSB will make it work as a fluidized sand bed, PH will drop ENORmously through the sand bed and the water out will have low PH and it will effect your tank.

secondly, the whole area would be oxygen rich, so no no3 to N action going on.

I had my DSB up for about 6 months, and WOW is all I can say, n and p both zero (cheato ws in place as well, no zeo and carbon dosing though)

I have a better way for you why not, feed a fluidized Sand bed with Oxygen poor water ? that would be same as what you are trying to do right ?

anyways, you are not examining anything here you are posting what u think and assuming its right and not taking others advice/ opinion into count.

further more. a reef tank has enough sources of no3, such as the live rock, and ... you certainly do not need to feed a tank with no3 of 100PPM with more no3

anyways, good luck ... .. if you use aragonite sand, u could say u made a calcium reactor water PH will fall throuhg the sand bed, and once it gets to last layer, it will dissolve the aragonite in and add calcium and KH and MG to the tank but will lower your PH.

Edit :

why are you testing for OPR ? what are is that going to show u ? ORP is NOT directly related to the amount of O2 in the water tested.

now lets say for some reason your Idea works, and lowers no3, it has to go somewhere right ? it would either be that the bacteria will starve from lack of Oxygen, so they will start stripping off oxygen from no3, that would mean u are left with Nitrogen ! which will get pushed into your tank, and will not have good effects ! OR :
it will start building up sulfur, and in terms hydrogen sulfite which again has no where to scape but back to the tank, right ?

I would like it if someone corrected me where is boomer

 

[S.A. Trev]

I have spent many years trying to perfect the DSB and found that the flow is as you correctly understand it one of the biggest contributing factors to how effective your dsb will function, My finds are that the most common ways of constructing a dsb which is simply setting it up between two solid horizontal dividers often results in a very ineffective DSB and infact more of a refugium. However I have found that providing a constant flow over the dsb just slightly less than what it takes to disturb the substrate is best.

1st I will explain why the solid divider is not a good option: With the solid divider you end up creating a dead ( no flow ) area over dsb as most of the flow is stopped and you can only expect some movement in aprox the top 25% of the water level above the dsb, what is most likely to happen here is that 80% of the sediment which falls into this chamber will see this dead area and end up settling on top of your dsb which is not a good thing, so from this you can under stand the you need flow from the dsb substrate level right the way up to the top of the water level in this dsb chamber

The following has been the most effective means of achieving this constant flow needed:
If you were to construct the two dividers between the dsb using perspex you mark the high of the substrate on the vertical line and up to the top water line of this chamber then using the appropriate tool you cut aprox 2.5mm wide slots going up from the substrate line to the top water line ( I find that using an angle grinder with a 2mm cutting disk works very well ) I allow a 10mm gap between slots. Now when the water flows it creates an even flow from the substrate level all the way up and will not result in any dead areas and will highly reduce the amount of sediment allowed to settle on your dsb.

An important side note to remember is that the food source for you dsb you are not able to see with the naked eye and that any sediment which settles on you dsm will result in a nitrate build increase, never put any type of hermit crab, shrimp,sand dwelling start fish,lobster or any fish in your dsb chamber this is often done and unfortunately what is overlooked is the fact that these creatures will consume the good creatures which have taken 6 months to mature in less than a week leaving a big hole in you natural filtration and may cause some big issues

I really hope this info is useful to anyone wanting to setup a dsb.

Trev

 

[Allmost]

Trev, I like your post, but one question

if the DSB is full of life, stars, worms, .... , then they will consume the detritus that is being deposited on top of the DSB, no ?
(I understand there are 2 schools of thoughts on this)

but other than that, I completely agree, the higher the flow OVER the DSB the better it functions. key word is OVER though, not through.

 

[crazylegs]

secondly, the whole area would be oxygen rich, so no no3 to N action going on.

How would a slow flow thru a five gallon tank full of sand result in an oxygen rich environment?

the bacteria will starve from lack of Oxygen, so they will start stripping off oxygen from no3, that would mean u are left with Nitrogen !

Isn't this the driving theory behind the Jaubert method, DSB method, and the Berlin Method? Isn't Nitrogen pretty much harmless as it exits the tank in bubble form?

you are posting what u think and assuming its right and not taking others advice/ opinion into count.

That's the pot calling the kettle black!

Bioload- Keep doin what you're doin. If there will ever be an end to the DSB madness, it will be a well documented, indesputable resolution derived only from experiments conducted in closed systems such as yours.

and lastly,your diagram is NOT DSB !!! that is fluidized sand bed

Fluidize - Fluidization (or fluidisation) is a process similar to liquefaction whereby a granular material is converted from a static solid-like state to a dynamic fluid-like state.

 

[Allmost]

secondly, the whole area would be oxygen rich, so no no3 to N action going on.

How would a slow flow thru a five gallon tank full of sand result in an oxygen rich environment?

your right, poor choice of words, not Oxygen RICH, but it will still have enough oxygen.

I really do not understand what the DSB madness means, alot of ppl claim they dont work ! while the ones using them see it work !

by no means I'm saying dont do it, hell this may become the newest and best way I'm all up for experimenting, of course with discussions lol

I really dont understand your last comment. fluidized sand bed, pushes water through sand. this project is pushing water through sand bed, so me calling it that


the way I look at it, lets say u have a large tank, and you place 6 inch of Sand bed at the middle, and fill it up with water so there is water under and over the DSB, drop food coloring on top, red lets say, hours later, the water beneat the sand bed will become red color, this way, the water on top layers will have Oxygen and at lower layers will be oxygen free. if you PUSH the water through, it will force Oxygen deeper down.

hmm now how is he gonna make the sand stop going out of the 5 G tank ? hmmm

 

[S.A. Trev]

Trev, I like your post, but one question

if the DSB is full of life, stars, worms, .... , then they will consume the detritus that is being deposited on top of the DSB, no ?
(I understand there are 2 schools of thoughts on this)

but other than that, I completely agree, the higher the flow OVER the DSB the better it functions. key word is OVER though, not through.

Hi Almost, yes most definately two schools of thaught with regards to this issue and I firmly believe that we strive to achieve a good steady flow over the dsb in order to not have particalssetteling on the dsb thus eliminating the need for these type of creatures such as hermits and shrimps ect in a dsb

Trev

 

[Allmost]

Hi Almost, yes most definately two schools of thaught with regards to this issue and I firmly believe that we strive to achieve a good steady flow over the dsb in order to not have particalssetteling on the dsb thus eliminating the need for these type of creatures such as hermits and shrimps ect in a dsb

Trev

hermit crabs and shrimps are different than tiny stars and bristle worms and ... that form in DSB

some pics can be found at the bottom of the page :
http://www.reef-eden.net/DSBs.htm

 

[S.A. Trev]

hermit crabs and shrimps are different than tiny stars and bristle worms and ... that form in DSB

some pics can be found at the bottom of the page :
http://www.reef-eden.net/DSBs.htm

Sorry bud I miss understood your question but here goes, well we will never stop all the sediment from setteling on the dsb and of course a small amount will settle and these guys will consume that, but even if you look at the size of these nutrient particals they are so tiny, also these worms will consume some forms of bacteria aswell as the entire dsb once matured is an ecosystem but the ballance is vital. Example would be to much nutrients = a nutrient consuming org such as worms multiplying faster than the bacteria which the worm lavea feed off and the end result will be too little bacteria and this is often called a dsb crash, but many dont realize what the real issue is and it most often starts with alowing to much nutrients to settle on the substrate

Trev

 

[TheFishMan65]

I think according to the thread ruprecht posted, the theory is that if you allow critters and sediment to settle in the sand bed there is a larger risk of a crash. The idea behind the hi flow OVER the bed is that nothing settle and all you get is bacteria. I am trying to remember what they said about sulfur. But I think part of that was with nothing to stir up the bed it won't get into the system.

So just to clarify I think there are probably more than 2 schools of thoughts. So can someone spell them out.

Allmost, why does everyone always use red food coloring? What wrong with blue or green? I can understand no yellow it can be hard to differentiate from fish - well you know

 

[S.A. Trev]

Hey fish man I do agree with you half way ( why does that happen so often , maybe a good thing ) yess you dont want sediment to settle but there is never a dsb that will have 0% sediment setteling there will always be some, now on the worms present they actualy play a very vital role in the dsb besides comsuming the nutrients which have settled they also move ( push ) the micro organic nutrients down deep into the dsb to where the various types of bacteria thrive and can consume these micro organics so with out a certain number of wormies this process will not happen, and again with to many you will have an imballance this is why a dsb needs to mature slowly and the ballance is vital to much of one orto little and its a disaster

Trev

 

[bioload]

Thanks all for you input and please keep it coming. So far we have reinforced all the things that I’ve read regarding the subject and in order to clarify the process (at least in my head) I would like to simplify things.

The first Question is will a DSB (just sand) added to a container reduce nitrates? May not be a simple yes/no answer, and maybe it is, but I would like to attempt to answer the question in a somewhat controlled manner. In order to answer that question I’m setting up the diagram above. Flow will be slow..VERY SLOW…Water will be flowing “through” the bed in order to isolate a sample for testing. And I’m hoping this would provide an answer to my question a lot sooner.

Hope that makes sense.