DSB in a bucket for nitrate control

[trmiv]

I'm getting ready to set one of these up on my new 90g. What I can't decide is, what to do with the sand in the tank? I was going to do a DSB in the tank, but that seems superfluous with this remote DSB. I can't stand the look of barebottom, so I will have sand. Should I stick with like 1" or under of fine sand, or go with coarser sand that I can vacuum regularly. The sand will obviously just be for looks since the DSB bucket will be handling the denitrification chores. I just don't want the sand in the tank to become a problem.

[foxthorn]

Originally posted by Anthony Calfo
...
To be clear here.... we are talking about about a remote DSB processing nitrates already in the water (solution)... not solid matter....

Anthony or anyone else for that mater.... Help a guy out here and fill me in on 'how' exactly does passing a strong flow of water over top of sand remove the nitrates? And why is any particular depth of the sand important? Sorry if this seems like a beginner type question - and I'd imagine there is must be some science behind it... but I got to know

TIA

[captbunzo]

Originally posted by trmiv
I'm getting ready to set one of these up on my new 90g. What I can't decide is, what to do with the sand in the tank? I was going to do a DSB in the tank, but that seems superfluous with this remote DSB. I can't stand the look of barebottom, so I will have sand. Should I stick with like 1" or under of fine sand, or go with coarser sand that I can vacuum regularly. The sand will obviously just be for looks since the DSB bucket will be handling the denitrification chores. I just don't want the sand in the tank to become a problem.

I'll give you my opinion, for what it is or is not worth.

First, your concern regarding sand (IMHO) is less about how much, and more about grain size and how you are going to keep detritus from settling. Two easy answers:

   A. Small Grain
   B. Keep up the flow.

And so this seems to be relatively independent of the amount of sand you put in the tank. So, personally, I would focus on the magic 30-40x diffused flow.

And then, based on budget, I would put 3-4 inches of sugar sized sand. You can go with less. For ME, that is an aesthetic thing, and about providing a place for critters to live in the display tank sand, sand for a goby, or whatever else you decide to go with.

Just my two cents!

[trmiv]

If I put 3-4" in the display, then I'm suddenly in DSB territory, and I would have to deal with the potential problems that brings.

[Anthony Calfo]

display DSBs are generally hard for most folks to finesse. The methodology is not flawed... just the application by most folks. That is to say... most aquarists build their rock structures against one or more sides of the aquarium (severaly handicapping water flow and leading to excess accumulation of solids/sinking in the DSB in time. Most aquarists also stock too many fishes... too early and/or over feed them... and most aquariums lack enough flow or enough of the right kind of flow. and have too many dead spots instead. All of theses things and more lead to the avoidable pollution of a substrate (regardaless of depth or grain size). Yet the reality of it is that most folks are NOT cut out for a display DSB. So as much as I like using them, I rarely recommend them or any but the most well-read/experienced/competant aquarists.

So... we have the RDSB option.

As for how it works... I'm really not sure what more there is to say. It is staggeringly simple as Paul has pointed out.

Focus on grain size (fine and small to prevent easy penetration of solids into tyhe bed) and maintain enough water flow to do the same. Nitrates already in solution are utilized by denitrifying faculties in a way similar, you might say, to the way our corals draw various dissolved elememts from the water (calcium, ammonia, etc from solution).

I can't say it any better/clearer. It really is that simple and cheap to do. Not rocket science here.

To alleve your dounts/fears... you might even take a temporary RDSM bucket and set it up in front of your aquarium on the floor being fed and returning on a short loop to/from your sump. Let it sit there for a month and watch your nitrates go down. If they do... then considcer a permenant installation (where/how). If it doesn't... then contemplate why (come back and ask detailed questions based on real experience and a real application) or... you can just take it off and think I'm full of it Either way it will only cost you less than $20 in materials likely. A small investment for a potentially significant return (nitrate reduction... less water changes for not having high(er) nitrates... better aquarium health, perhaps less nuisance algae and time saved for not manually treating it, etc.). Lord knows you've/we've wasted far more money on other things... like killing fishes or corals because you don't have a QT tank

[trmiv]

Oh I have no problem with the RDSB, that is going on my tank for sure. I'm sold on the concept.

What I'm trying to decide is since I'll having the RDSB taking care of my denitrification issues, I won't have to depend on a tank DSB for that. So where do I go with sand in the display? A short coarse sand bed that can be vacummed regularly? Short fine sand bed and disturb it regularly? Barebottom?

[Anthony Calfo]

I would suggest minimal sand in the display for the low-maintenance option and safe bet, indeed. Larger grains for high water flow tanks... finer sands if you can (using a CLM or like diffused water flow versus streamers or the like). Whichever you choose... keep it well under 1" depth IMO

[trmiv]

Thanks, sounds good. I'll probably go with something like the CaribSea Bermuda Pink Reef Sand. It's 2-4mm, which is a nice larger size. For some reason I do like the look of tanks with the larger sand, that has slightly different colors in the grains.

[nickyblase]

After reading all this, I've decided I'm going to do one, but need some design advice, as my space is a little limited.

I would like to put this in my stand under my 38G, but the stand of course isn't huge. What I was thinking I would do is put in a 5 gallon salt bucket as the first to receive the h20 from the display with the skimmer in it to grab as much solid as possible, then have the side of the 5g drilled and a tube gravity feeding h20 into a 2g bucket filled within a few inches of the top with sand, and then (if I've got enough room), have that gravity feed into a small refugium and up into the tank again.

Will this work? As I look at one of my 2 gallon buckets that I use for water changes on my nano, It's about 10" tall by 9" in diameter.

If this isn't enough to support a fairly heavily stocked reef tank, I could probably fit 2 5 gallon salt buckets inside the stand, but would then have to find a way to combine the sump bucket as a sump/skimmer holder, and somehow put a small fuge in it.

Does anyone have any ideas?

[Spuds725]

A picture of your buckets inside the stand (without plumbing) might help see this (your plan). It sounds like it would work but you obviously need enough room to service your skimmer-- might be a problem if that bucket is elevated.

Also, any considering using buckets for sumps, RDSBs, etc-- the square plastic kitty litter container buckets they sell will more then likely help you utilize space better then traditional round buckets..

This is a shorter one, but they do have taller ones

Originally posted by Dag
Anthony,

Do you care to comment on the theory of why the remote DSB works. Some have argued that it can't work because in order for the DSB to work, water has to move through it, and for water to move through it, critters have to live in the DSB, and for the critters to live they have to fed, and not enough food gets to the DSB unless you specifically feed it, and feeding a DSB is adding unnecessary pollution.

Experience often trumps theory, but wondering if you had a countertheory, or have an opinion as to what is the weak link in the foregoing chain of reasoning.

I haven't used this method yet but I might as I feel like I am starving my fish all the time so could increase my feeding level a bit....

Regarding how it works I think it might just be an issue of nitrate concentrations in the water at the top and bottom of the sandbed.... let me walk you through my reasoning-- (I majored in Chemistry in college and it kind of goes along with thermodynamic principles--finally a use for that awful Physical Chemistry class I had to take).....Realize this is mainly me just postulating and making assumptions on how it might work-- I have no direct experience with this method or research on how it actually works...

I'm assuming you will agree that the sand at the bottom of the bed is wet so the water has penetrated to the bottom.... now in relationship to the sand grains, the water and nitrate molecules are easily much smaller then the smallest of the sand grains so it should not be an issue for them to be able to move down and around the grains-- now we get to the issue of how do the nitrates penetrate if the water isn't moving down through the sand bed....

IMO its simply being diluted from a region of higher nitrate concentration to lower.... initially when the sand bed is added, the water in the sand bed will contain nitrates.... as DE-nitrifying bacteria form and start consuming the nitrates the concentration of nitrate in the water at the bottom will decrease -- this difference in concentration is what would be driving the nitrates through the sand bed--

The second law of thermodynamics states is kind of set of principles but is pretty well reflected by

"The most concise statement of the second law of thermodynamics states that the total entropy of any isolated thermodynamic system tends to increase over time, approaching a maximum value."

This is from this website-- http://en.wikipedia.org/wiki/Second_...thermodynamics --

You should try to think of Entropy as disorder-- this is what drives dilution in liquids and gasses-- think of it as an odor or aroma that spreads around a room lacking circulation-- thermodynamic processes a driven by increasing disorder since this is the lowest energy state--- dilution occurs because of this...

the same applies to liquids... put anything that dissolves in water and even without circulation, the concentration of that substance will eventually equalize throughout the volume of liquid, barring any external force..

Now since the nitrate is being consumed in the sand bed, the naturual tendency would be for more nitrates to move into the sand bed and further be consumed as this lowers the energy state of the nitrates in the water.... so the nitrates are continually pulled into the sandbed as they are consumed...

I hope this makes sense to those that read it...

once again... this is mainly just my thoughts on the subject and not based on any actual experiments or research....

and as Anthony pointed out... it works, how doesn't really matter...

[Fmellish]

I have a fairly large refugium in the middle of my 30 gallon sump. I have a 120 gallon tank with about 500 gph running through my sump. Can I do a remote deep sand bed in my refuge?

i'd much rather have a DSB in my refuge, and then a shallow sand bed in my display.

This may have already been covered. Thanks for any response.

Josh

[nickyblase]

would one of those kitty litter buckets be big enough for a dsb on a 38? If so, I'll use one of those inside a larger rubbermaid for a sump, and then figure something out for a refugium - maybe a hob if I can't fit one inside the stand.

[foxthorn]

Spuds.... Thank you for posting that reasoning and your thoughts -- you've really gave me something to think about and further research. Do you have any thoughts on how the depth of the sand bed relates? Does a deeper sand bed 'draw' the nitrates faster or would a somewhat deep bed that has more surface area 'draw' more nitrates ??

[Spuds725]

Originally posted by foxthorn
Spuds.... Thank you for posting that reasoning and your thoughts -- you've really gave me something to think about and further research. Do you have any thoughts on how the depth of the sand bed relates? Does a deeper sand bed 'draw' the nitrates faster or would a somewhat deep bed that has more surface area 'draw' more nitrates ??

IMO-- The depth should not matter as much as its ability to "host" denitrifying bacteria and the overall denitrifying bacteria population of the DSB-- the nitrate concentration should decrease down to zero as you go deeper and deeper into the sand bed... as long as you reach zero (at some point above the bottom of the sand bed)... a zero concentration of nitrate (at some point in the sand bed) should be all that is required to maximize the rate at which the nitrate in the water column difuses into the sand bed-- the sand grain size and type still might play a role in the rate-- really the only way to check this would be to set up some tests of different identical remote DSBs and start varying things between them (types and sizes of grains, water flow, even temperature) and start measuring nitrate concentrations at different depths of each bed to see the differences...

The area of the sand bed should affect the ability and the rate of the nitrate to penetrate just because there should be more area for the nitrate to diffuse into (a larger area should be able to accept more nitrate)-- this should facilitate the rate of diffusion into the bed

I really don't have enough knowledge of what actually occurs in the bed to have an opinion on what might affect this.... the purpose of my post above was to try and provide some logical explanation of what is occuring and what drives the movement of nitrate into the sand bed.... most of us have trouble seing these things on the sub-microscopic level...

once again, all this is not based on any actual experience, reading, or research... this is more of me postulating on what should be occuring based on my understanding of physics and chemistry when applied to this application.... its rare you actually can apply some of these principles to real life situations

would one of those kitty litter buckets be big enough for a dsb on a 38? If so, I'll use one of those inside a larger rubbermaid for a sump, and then figure something out for a refugium - maybe a hob if I can't fit one inside the stand.

IMO yes-- they are about the same size as a 5 gallon bucket, just better shaped for use under a cabinet (it should hold a larger volume for a given height and width)--- I use one of these buckets to transport water from my RO/DI container to my tank and the small one I use should hold about 5 gallons-- 2 1/2 gallons fills it about 1/2 way-- and it seems plenty strong for this use.

[A.G]

Its been a while since I have posted anything. Well, just to let you guys know I have actually stopped measuring No3 since the test kit I use cant detct it . I have checked the DSB and it seems clean with no dirts. Why am I doing water changes again ?

A.G

[Anthony Calfo]

The update is very much appreciated my friend! Thank you. Indeed, it sounds like its working as it is intended... with fine sand and adequate water flow, solids do not penetrate/accumulate and the NO3 from nitrification in the system is utilized/reduced as expected

As for the water changes (I know you were joking... but I'll point out here for the newbies), we continue to do them because there are numerous known and unknown accumulating elements to degrading/aging water that must be diluted which have little to nothing to do with the DSB bucket processes.

Thanks again for the fab news AG!

[nyvp]

quick question for 700g tank. Do i want depth or length. what I am asking is is it better to go with a 55g trash can or 55g tank?

[Anthony Calfo]

either will work, but I'll suggest the length instead.

[Teremei]

Originally posted by trmiv
Thanks, sounds good. I'll probably go with something like the CaribSea Bermuda Pink Reef Sand. It's 2-4mm, which is a nice larger size. For some reason I do like the look of tanks with the larger sand, that has slightly different colors in the grains.

I'm going with something simular to that too. I reccomend 1" too, that way any niusance areas can be completely replaced easily. And you can still have snails and crabs. So. I just found out about this method and will consider using this under my tank. Can someone please draw me a mental picture of how to set this up/what equipment I will need? (sorry I did not read all 10 pages)

[Anthony Calfo]

"Can someone please draw me a mental picture of how to set this up/what equipment I will need? (sorry I did not read all 10 pages)"

Teremei... I promise you that your aquarium, livestock and education in this hobby you will get by being resourceful and not asking to be spoon-fed are well worth the time taken to read the free content assembled here for those very purposes (improving you and the health of your livestock).

It would also be respectful to us and our our time if you'd kindly just take the time to read it.

I do appreciate your honestly in saying you did not read the thread. Please do understand that I am more interested helping you be a better aquarist if nothing else by making the effort to use the tremendous wealth of knowlege that is in this free content archive that we call Reef Central.

You will answer your questions and learn so much more in the process for forming such (good) habits.

[Fish'InMN]

First off, I just finished all 10 pages, and wow that's a read. It reads like you guys have pretty much hit the jackpot for removing nitrate. This is especially nice to see, since I'm starting plans for a 30g right now that had originally included a 10g sump/refugium. Now, you've got me thinking about a RDSB, and how I can turn that 10g into one. I assume I'd have to make it water-tight, to turn it into a part of a closed loop?

Great thread folks, I hope you don't mind the newbie asking Qs.

[Anthony Calfo]

all good Fish'InMN

And welcome to RC!

As for your 10 gall sump plan... you might just take a small bucket next to the sump and prop it up (with a hole drilled at the top for the overflow) to be slightly above the height of the sump. This way, you do not have to handicap refugium or sump-proper space.

Power it with a small powerhead in the sump that feeds this RDSB on its own little loop.

[Teremei]

Originally posted by Anthony Calfo
"Can someone please draw me a mental picture of how to set this up/what equipment I will need? (sorry I did not read all 10 pages)"

Teremei... I promise you that your aquarium, livestock and education in this hobby you will get by being resourceful and not asking to be spoon-fed are well worth the time taken to read the free content assembled here for those very purposes (improving you and the health of your livestock).

It would also be respectful to us and our our time if you'd kindly just take the time to read it.

I do appreciate your honestly in saying you did not read the thread. Please do understand that I am more interested helping you be a better aquarist if nothing else by making the effort to use the tremendous wealth of knowlege that is in this free content archive that we call Reef Central.

You will answer your questions and learn so much more in the process for forming such (good) habits.

Anthony, no offense taken. I have had a reef tank up and going for near a year now. I understand the process of denitrification, all I am asking is what pumps, and or products I will need to connect this to my new tank.

But your right, I should probably read the whole thread. I stopped at page 2. I fully understand the concept, but I have yet to see a link to a diagram. All I've read so far is to make water move briskly over a DSB in a bucket. Nobody had mentioned what sort of pumps they were using (atleast up to page 2)

I am currently planning a 90 gallon. Luckily for me I have room for it and I can slowly set it up while still keeping my 55 running. The first thing I am going to do is find the perfect sand (maybe just up to 1 inch). The mistake I made with my first tank was adding 5" of gravel (this is a terrible newbie mistake that I will not repeat).

I will bring up this remote sand bed up to my custom sump maker, and make this a part of my sump when I do ditch the wet/dry my 90 comes with.

[Fish'InMN]

Originally posted by Anthony Calfo
all good Fish'InMN

And welcome to RC!

As for your 10 gall sump plan... you might just take a small bucket next to the sump and prop it up (with a hole drilled at the top for the overflow) to be slightly above the height of the sump. This way, you do not have to handicap refugium or sump-proper space.

Power it with a small powerhead in the sump that feeds this RDSB on its own little loop.

Ah, I see. I will have to figure out what bucket size will fit, but it sounds like a 5gal is what everyone is using. I don't have any use for Kitty Litter, but maybe that type of bucket will work best.

Thanks a bunch for the ideas folks, I'm sure I'll be back with more questions sometime!

Regards,
Marty

[AnnArborBuck]

Wasn't there an article in one of the recent Reef Magazines (hard copy, not Reef Central's, it's a yearly mag) that talked about DSBs. In particular, they discussed a new system that was being tried that that implemented a remote deep sand bed with a a plenum. In this setup, the author flowed the water through the plenum and then the water would be forced to flow up though the sand. He used red dye to track flow of water through the sand to see the movement of the water. From what I remember the experiments went pretty well.

I actually like this idea better because then you don't have to worry about creating a plenum, solids in the plenum, etc.

Diffusion at it's greatest, so simple, yet so powerfull.