RDSB - Remote Deep Sand Bed Benefits - 2014

[Reef Frog]

Just curious:

This thread makes a few references to the DSB or RDSB providing "coral food". So what kind of food for what kind of corals? And, will that make any kind of real difference? Are we talking free swimming zooplankton or self perpetuating phytoplankton getting into the water column?

I can see the potential benefits of nitrate processing and isopod production for fish. But do you think enough (or any) free floating phyto or zooplankton is really produced to help hard to keep filter feeders like fan worms, sponges, NPS filter feeders etc?

It seems like a lot of effort if the goal was just to just produce "coral food" for stuff like all the popular LPS & SPS species, which are kept in perfect health in thousands of aquariums worldwide with no refugiims and bare bottoms.

So what kind of non-substrate bound micro fauna or flora will these DSBs produce in what quantities...and has this been proven?

 

[ca1ore]

What do you guys think of this?
My main sump is a 150g Rubbermaid tub.
Right now i have a skimmer box inside it, sitting on two plastic egg crates.
Around that, is a bunch of live rock.
What if I did a deep sand bed in this tub? It would kinda be a remote sand bed in the way of not being in the main display where it could remain relatively untouched.
And i could have A LOT!
I would just need to plumb in an elbow and a vertical extension to the drain so it would reach above the sand bed.

Here's a couple pics so you can see.

Ignore the white pvc. That was my attempt to add more flow in there but I don't think its really doing much so I was going to remove it anyway.

Very cool! I like the refugium/frag tank. Dose the former overflow through that slot into the latter? Did you make it yourself? Only thing is that you don't appear to actually have is, ahem, .....a display :lol:

Sorry, just amusing myself ....greatly!

 

[d2mini]

Dose the former overflow through that slot into the latter? Did you make it yourself?

Yup, the return from my chiller feeds the fuge which then overflows into the frag side which then drains back into the big sump. I designed it but had a buddy build it for me. It was brand new there, but now where the water is flowing down the wall, it's covered in algae. It's like my own little algae scrubber.

The 200g display is on the other side of that wall, where the three Bean Animal drains are coming out.

 

[xdestry]

wow d2 mini that setup must be for a really big tank. i am just starting in this hobby cant even imagine what it takes to set something like that up. here i am trying to think of what to do with a 2000 dollar budget lol

 

[atrox]

Holy cow I could tinker around with that set up all day, simply put it's awesome! My wife complains about the amount of time I spend on my small 40 gallon so if I had that I'd be single. I've always run a dsb, a natural approach and keeps me out of the gfo band wagon. If it's remote I say try it, if it dosnt suit your needs or achieve the outcome you want take it offline. More than one way to skin a cat, and just think of the additional livestock or mangroves you could put in there. Btw that desk with chair is the icing on the cake, I'd feel like Jacque Cousteau doing my water samples.

 

[d2mini]

wow d2 mini that setup must be for a really big tank. i am just starting in this hobby cant even imagine what it takes to set something like that up. here i am trying to think of what to do with a 2000 dollar budget lol

LOL, it's a 200g. Not all that big.

Holy cow I could tinker around with that set up all day, simply put it's awesome! My wife complains about the amount of time I spend on my small 40 gallon so if I had that I'd be single. I've always run a dsb, a natural approach and keeps me out of the gfo band wagon. If it's remote I say try it, if it dosnt suit your needs or achieve the outcome you want take it offline. More than one way to skin a cat, and just think of the additional livestock or mangroves you could put in there. Btw that desk with chair is the icing on the cake, I'd feel like Jacque Cousteau doing my water samples.

So is your dsb in-tank?
What is the longest you've run a dsb continuously in one tank?
Do you do any sort of maintenance on it? In the article posted above I believe there was mention of "feeding" the dsb.

 

[atrox]

I've maintained the same in tank dsb in a 135 since 2008 6-8 inches that I transferred some into a 40 breeder. I've always gravel vac'ed routinely and will continue to do so. I run filter socks but remove when I feed display so organisms in get excess routinely. Vac on dsb had never caused any problems and firmly believe this has kept the problems oftenly seen in dsb at bay. I've always had bristle worms by the hundreds, and love them, as well as nassarius snails to constantly move the bed.

 

[d2mini]

But doesn't vacuuming the bed defeat the purpose of a DSB?

 

[atrox]

Here's a good thread pay note to "elegance corals" response. The general idea I agree to is at some point waste will reach a level that just can't be broken down any further by bacteria and at some point this waste needs to be manually removed. I don't gravel vac every water change, I do it in sections of the sand split into 1/4s. One 1/4 every 2 weeks and rotate so I don't shock the system. You'll be surprised how much gunk comes out.


http://www.reefcentral.com/forums/showthread.php?t=1733398&page=3

 

[d2mini]

I'm not surprised at all by the "gunk".
But I still don't understand why you would bother with a DSB if you are going to vacuum it.

 

[atrox]

I understand where you are coming from I thought the same lol. Look at like any media with the exception of live rock whether it's carbon, gfo, purigen, it all has to be maintained or replaced. The idea if just leaving the dsb alone when I first got into this hobby 20 years ago was to "just leave it be and don't touch it, or it will explode!" That trend turned into bb tanks, plenum tanks, and all kinds of other ways to skin a cat. They do require maintenance and I'd rather suck a little sand then have to buy or mess with gfo or carbon. The ocean constantly removes detritus from the sand and brings in a continual source of replenishment water. As much as I would this type of setup its all just a stagnant box.

 

[atrox]

http://www.reefcentral.com/forums/showthread.php?t=2311177

 

[S2minute]

RDSB - Remote Deep Sand Bed Benefits - 2014

Get that little book...

http://www.ronshimek.com/deep_sand_beds.html

Also these....

http://www.dynamicecomorphology.com/depublish.htm

I used a modified version of this. I used South down play sand that was sold @ Home Depot. It's prob sold under a different name now. If you use that in a RDSB, the grain size will be small enough as to prevent most larger sized waste from migrating into the bed. Besides, not much more than very small particles of food and waste should be able to make it that far from the main DT anyways.
I've had my RDSB up and running since 2008 and I've never had to vacuum it. The grain size and texture is perfect to begin with. The worms, bac and other critters do the work for me. Get those books and work your RDSB around the info you find in them. I did and it works for me

 

[d2mini]

I understand where you are coming from I thought the same lol. Look at like any media with the exception of live rock whether it's carbon, gfo, purigen, it all has to be maintained or replaced. The idea if just leaving the dsb alone when I first got into this hobby 20 years ago was to "just leave it be and don't touch it, or it will explode!" That trend turned into bb tanks, plenum tanks, and all kinds of other ways to skin a cat. They do require maintenance and I'd rather suck a little sand then have to buy or mess with gfo or carbon. The ocean constantly removes detritus from the sand and brings in a continual source of replenishment water. As much as I would this type of setup its all just a stagnant box.

Right, i hear what you're saying.
So let's say you are right and that a dsb HAS to be vacuumed.
That still leaves me with the question of why have a DSB and not just a regular sand bed? Seems to me that vacuuming would remove the good with the bad.

 

[S2minute]

Get that little book...

http://www.ronshimek.com/deep_sand_beds.html

Also these....

http://www.dynamicecomorphology.com/depublish.htm

I used a modified version of this. I used South down play sand that was sold @ Home Depot. It's prob sold under a different name now. If you use that in a RDSB, the grain size will be small enough as to prevent most larger sized waste from migrating into the bed. Besides, not much more than very small particles of food and waste should be able to make it that far from the main DT anyways.
I've had my RDSB up and running since 2008 and I've never had to vacuum it. The grain size and texture is perfect to begin with. The worms, bac and other critters do the work for me. Get those books and work your RDSB around the info you find in them. I did and it works for me

Right, i hear what you're saying.
So let's say you are right and that a dsb HAS to be vacuumed.
That still leaves me with the question of why have a DSB and not just a regular sand bed? Seems to me that vacuuming would remove the good with the bad.

Get that little book...

http://www.ronshimek.com/deep_sand_beds.html

Also these....

http://www.dynamicecomorphology.com/depublish.htm

First one will answer all your questions D2mini and it's cheap. If your going to set up a remote DSB read that. That's all there is to it but, you have to start with the right stuff first and then resign yourself to NOT mess with it.

 

[vlangel]

I have a DSB in my current display tank and have always used DSBs in my tanks. My boss at a lfs was a believer in them and in turn convinced me of their effectiveness in dealing with nitrates in particular. My current tank is fairly heavily stocked and yet I never have detectable nitrates. When I was younger I didn't like the 'dirty' appearance of them in a DT but now I rather appreciate the gas bubbles, worm tracks and coloration that characterizes a working DSB. Another reason I used them was one has a buffer against a toppling rock in the tank. I am sure none of you are clumsy but I worried about such things.LOL

 

[codyreed29]

I have tried a few different filter types. I have had a dsp on my new tank for about 4 minths and it and liverock have tken care of my tank. No nitrates thus far 4 months. I have added cheato mangroves and other algea. As well as mud. The only filtering I have and it has al but a bit taken care of hair algea. I plan to have a large rdsb refugium on my next tank.

I would suggest using the finest sand you can get. like 1/8 mm or less. Mud is about 1/16 mm to give you an example. The finer the better thru biology research. I have seen a large change with the addition of dsp and mud. 33 tank with 8 gallon dsp refugium.

More open and growth.

 

[saf1]

I've always run DSB ranging from 6 to 9 inches. When I had my 100 gallon and now in both of my 29 gallon bio cubes. There is a lot of chatter about DSB's being good and bad with everything in-between. At the end of the day it isn't any different, to me, than not doing water changes every week, etc.

I don't vacuum mine nor do I have any creatures that would eat any of the organisms in there but I know there are a metric ton of worms and other things doing their thing. I also have some clams that live in there which is how I get the turn over. Mini stars, bristle worms and other things all help control the build up that happens over time on the surface (has does water flow).

I don't do remote beds because I like the natural look. My 100 gallon was up over 7 years. It crashed due to a power outage when California's power grid had some political issues. Believe it or not the rocks and sand is what survived and some zoa's. All of which I've since dispersed in my small tanks.

 

[jdmneon]

hey, I just wanted to Chime in on this old thread because I find this topic fascinating

some of the earlier posters were absolutely correct about the Phosphate and Nitrogen cycles, a deep sand bed will act as a sink for both N and P, if nothing is taken out of this sink, organic material will accumulate until the sink is full (and it is no longer a sink). So logically a deep sand bed, if left completely undisturbed will crash eventually (crash meaning it will stop being a sink for nitrogen and phosphate in your tank and instead start to become a problem)

cleaning it will slow this process but it won't stop it, eventually all of your aragonite will have as much Phosphate attached to it as it can hold

all of the above is well established Science based on an understanding of the Phosphate cycle.

now here is the part where there isn't enough data to really make a meaningful conclusion

does this process happen on a timescale that is relevant to the saltwater aquarium hobby?
for example does it take a year? ten years? or ten centuries? for six inches of aragonite to become completely phosphate saturated?

if it takes only a year, then a deep sand bed is a horrible idea, if it takes around ten years then a deep sand bed is fine for a majority although not all hobbyists, since by then most aquarists have bought new, larger tanks or left the hobby, if it takes ten centuries then a deep sand bed is a great idea for every hobbyist.

as far as I know, no study has been done, and it would be incredibly difficult and expensive to do such a study because of the sheer number of variables involved, how many Detritivores do you have? what species? how fast is phosphate accumulating in your tank? how often do you clean? how good is your skimmer? what temperature does your tank usually run at? what is the average particle size of your sand? the median size? the most common size?

it would take probably a decade of pretty intense scientific study and probably several million dollars to really answer this question definitively, and there is really no pressing need to answer the question since there are other proven methods of removing Nitrates and Phosphates from your tank these are:

-using a remote deep sand bed that you can offline quickly if it does crash
-replacing a significant portion of your sand-bed annually or bi-annually
-running an oversized skimmer without using sand at all
-using Chaetomorpha or some other Algae and then removing that Algae from the tank
-using a phosphate reactor(Expensive)

everything else is really anecdotal evidence and doesn't really mean anything, just because some aquarist had success doing it, doesn't mean it's a good idea, some people keep rays or sharks successfully in tanks that are like 1/10th the required size but that doesn't mean it's a good idea

 

[dkeller_nc]

some of the earlier posters were absolutely correct about the Phosphate and Nitrogen cycles, a deep sand bed will act as a sink for both N and P, if nothing is taken out of this sink, organic material will accumulate until the sink is full (and it is no longer a sink). So logically a deep sand bed, if left completely undisturbed will crash eventually (crash meaning it will stop being a sink for nitrogen and phosphate in your tank and instead start to become a problem)

This isn't necessarily so (though it could be under certain circumstances). In particular, the thought behind a RDSB is that certain types of facultative anaerobic bacteria will use nitrates as an electron acceptor in an anoxic environment, and the products of that process are CO2 and N2. So the RDSB, if operating as intended, isn't a sink for nitrates - it converts the nitrates to gaseous nitrogen which then leaves the system.

Phosphate is a little more complicated, but the basic idea is that in the process of growing/reproducing, the bacteria absorb phosphate as part of their cellular structure. These bacteria grow as biofilms, and the biofilms are continuously shedding bacteria into the water column. Skimming then removes the bacteria, which accomplishes phosphate removal from the system.

In my opinion, the major potential issue with a RDSB is the buildup over time of irreducible organic/mineral sludge, which if left unchecked, can "plug" the RDSB so that very little gas, water and nutrient exchange can take place. The adherents of RDSB therefore generally promote the idea of a "living" RDSB heavily populated by burrowing animals that ensures that this irreducible detritus is either ingested and converted into another form, or stirred into the water column where normal maintenance removes it.

My experience with carbon dosing suggests that the main advantage of an RDSB may not be all that relevant any longer, which is the prevention of the buildup of nitrate in the tank water. To me, carbon dosing is one heck of a lot easier to perform and monitor. That said, there may well be reasons to use a RDSB in the service of producing bacteria and other organisms as food for the creatures in the tank (such as an NPS tank, for example).