Siphon Your Sand Bed!!

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This has been a very interesting thread to say the least. LOL But informative as well.

For my tanks, I never clean the sandbed. I may on ocassion lightly swoop over the surface but thats about it. I mostly have DSB's in my tanks as well. I have found that with my circulation of water I dont often have much if anything to vacuum up.

If your vacuum thing into the sand arent you releasing all the nasty gunk that is built up in there? Like nitrates for instance? I also dont have any sand sifting stars so my sandbed is pretty much as it was when i added it.

Just wondering if I am doing the right thing. I also always advise people not to muck around in their sandbeds so I wanna be sure thats correct advice.

Thanks guys for the entertaining read thus far. Feels like I'm in college and have a massive technical reading assignment. LOL
 
Can't.. Read.. Anymore...

Ugh, this was a lot, but very informative. Obviously there is no direct answer to this subject and as always, there's more than one way to accomplish the same thing. I personally am tired of dealing with a sandbed and will probably do an sps only with no sand next time around.. Just seems a lot easier.
 
Renegade,

I think we agree overall about the subject, some minors things we have some different views but nothing wrong with that. Also this has been a great way to learn a new thing or 2 also.

Here is the one thing im not fully rapping my head around. Yes macro algae is a great form of phosphate and nitrate removal, however im unsure how you think these macro's are pulling phosphates out of your sand bed. We established phosphate in the sand bed will bind to sand, and under these conditions we also established sand and a definite lifespan based on the amount of phosphate it can bind/hold. So how is this happening where it becomes unbound regularly from the sand and freed from the sand bed to be taken up by macro algae. This is my biggest sticking point because technically the phosphate could remain bound in the sand forever.

Also as stated in the articles, the leeching process is slow and will not result in large amounts of phosphate being release from the sand. So under this logic im forced to assume that macro algae is not removing many phosphates from your sand bed. Maybe you could explain this for me if im missing something.
 
carey said:
If your vacuum thing into the sand arent you releasing all the nasty gunk that is built up in there? Like nitrates for instance? I also dont have any sand sifting stars so my sandbed is pretty much as it was when i added it.

Well if you siphon your sand bed on a set schedule then really you wont have much of that nasty gunk laying there to begin with. The problem with touching sand beds left for long periods untouched is the build up of noxious gases such as hydrogen sulfide.

If you wished to begin cleaning your bed i would recommend starting slowly and only the first 2" max should probably be touched. Doing this in 20% portions will help avoid any large gas releases the few times being siphoned. After this the bottom layers can be siphoned. Again its recommended to do small portions at a time to avoid large gas release and to avoid disturbing the entire denitrification of the sand bed at the same time. If that makes sense.

For people that are having nitrate/phosphate issues while running a DSB this is what I would suggest.
 
Marco V said:
I'm a newbie here , all this has me confused . The end result was that a DSB should be cleaned but not all of it , correct ?

All of it can be cleaned, however to reduce impact on denitrification and microfuana it should be done in smaller amounts over longer periods of time. Doing this will ensure reproduction of lost microfuana and oxygen to become depleted again from the disturbed layers.
 
crister13 said:
Ok, I have a 4-5" dsb but my sand is sugar sized grain. How should I clean it? It ALWAYS gets sucked up.

Sugar sized grain is the hardest to siphon buy ive found a way of dealing with it. The trick is using a siphon with a small diameter hose ( easier to pinch, and easier to control slow flow.

Pinching off the line before sand is sucked ip the line will allow it to fall and tumble releasing the detritus. When this happens, allow flow again momentarily, the detritus will suck up and the must again pinch the line to stop any sand from being sucked up. Its very difficult to explain and paint a picture. I may just have to do a video to show. However that might not be till friday or so when im due for a PWC.
 
I'm a newbie here , all this has me confused . The end result was that a DSB should be cleaned but not all of it , correct ?

Well I'm sorry to confuse you further, and Schism's answer will probably differ from mine, but the correct answer is that no your sandbed doesn't necessarily need to be cleaned, but yes it needs maintained. If you choose to employ the mechanical method of siphoning to try and reduce the accumulation of biodebris then you should vaccum no more than the top 1" to 1 1/2" of the sandbed. Do not vaccum by dragging, vaccum by pushing in, sucking up the gunk, and then lifting and repushing the tube back into the sandbed. Dragging will simply stir up the gunk and sand and cause it become suspended in the water column.

So what is the alternative? Biological cleaning by maintaining a healthy and diverse population of micro and macrofauna within your sandbed. How do you do this? Consistent exchanges of livestand and the benefical biofauna (need to be introduced multiple times per year - not a establish and forget it methodology). It can be done between tanks if you have multiple tanks, between friends or reef clubs, between you and a LFS (great source of diversity - every shipment has the potential to introduce new critters into the sandbed fauna - unfortantely occassionally you may get some not so great things), or by a sand exchange via shipping. For macrofauna, what you want are organisms that stir and consume debris, but not those that stir and consume the very fauna that you are trying to maintain. The difference is subtle, but it does exist.

Ok, I have a 4-5" dsb but my sand is sugar sized grain. How should I clean it? It ALWAYS gets sucked up.

I'm sure Schism will probably be better able to answer your question, as this is more his area than mine. However with sugar-sized simply skimming the upper surface first to eliminate things trapped on the surface is how I would start and then most likely you have to use something similar to the pinching method Schism described to prevent your sand grains from joining the exodus.
 
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Ok so my question is I have a dsb and I just do the top inch or so every pwc. In your opinion shism is that correct?
 
Hondatek said:
Ok so my question is I have a dsb and I just do the top inch or so every pwc. In your opinion shism is that correct?

Sure, what you are doing by siphoning the first inch will overall reduce the amount of organic matter that your sand bed needs to break down/convert/consume.

You could also take it a step further and siphon the lower portions in small sections over long periods of time. For example say 25% twice a year.
 
Ok well I just started doing it and my bed was unmaintained for a while so I'm just starting slow to avoid anything bad happening . Thanks
 
Hondatek said:
Ok well I just started doing it and my bed was unmaintained for a while so I'm just starting slow to avoid anything bad happening . Thanks

Post a pic, let is see the junk your collecting.
 
Will do next water change. It will be hard to see the bottom of the can since I do 30 gals at a time but I'll take a sample. Honestly I actually don't really notice that much besides the sand. But the tank has only been up since november so even tho I have neglected it since then it's not really that old and that might be why I'm not seeing much.
 
Renegade,

I think we agree overall about the subject, some minors things we have some different views but nothing wrong with that. Also this has been a great way to learn a new thing or 2 also.

Here is the one thing im not fully rapping my head around. Yes macro algae is a great form of phosphate and nitrate removal, however im unsure how you think these macro's are pulling phosphates out of your sand bed. We established phosphate in the sand bed will bind to sand, and under these conditions we also established sand and a definite lifespan based on the amount of phosphate it can bind/hold. So how is this happening where it becomes unbound regularly from the sand and freed from the sand bed to be taken up by macro algae. This is my biggest sticking point because technically the phosphate could remain bound in the sand forever.

Also as stated in the articles, the leeching process is slow and will not result in large amounts of phosphate being release from the sand. So under this logic im forced to assume that macro algae is not removing many phosphates from your sand bed. Maybe you could explain this for me if im missing something.

I think your issue is perhaps with your perception of concentration levels of phosphate. In order to understand the process you need a little background knowledge, I'm going to assume that you are familiar with the basic concept of diffusion of substances and at least somewhat with concentration gradient? In other words, we all understand that if the aragonite has a lower concentration of phosphate than the surrounding water, the phosphate will tend to move from the aragonite into the surrounding water. This is very similar to condition in which phosphate is found in the soil and is taken up by the root system of plants. In this case however, we are working with not roots, but algae cells either cellular or multicellular. As the organisms binds phosphate within its cells to form organic compounds the concentration gradiant becomes different then the surrounding water and therefore phosphate moves from the water into the cells. This creates a microenvironment around the cells in which the concentration gradient in the surrounding water is lower than the concentration bound into the aragonite, and thus allows the phosphate to move from the aragonite back into the surrounding water. That is a huge oversimplification of something that involves both biological and chemical processes, but conveys the general idea.

Additionally I'm not sure that your quite getting the concept of removal of phosphates from my perspective. You're focuses on preremoval via mechanical means (i.e. siphoning). I also focus on preremoval however my means are biological rather than mechanical, although like you I also rely on the protein skimmer to remove biophosphate. Once phosphate is introduced, lets say via feeding, you siphon off the excess or left over decaying food. I allow other organisms both macro and microfauna to consume those left over substances. I suppose that I also should point out that I typically have systems that have a very light bioload from a fish perspective, but it is the same principle that is applied in the large aquarium tanks in public aquariums. Nobody goes in and siphons those tanks, they relie heavily on mechanical removal via protein skimming and biological removal via fauna. Once consumed (assuming that you are not overfeeding) these phosphates become bound up as biophosphate which your skimmer will remove. Inorganic phosphates are absorbed and bound by the biological process of photosynthesis. Once phosphates are bound within the organic tissue, removal of that organic tissue (algae harvesting) results in the removal of that phosphate material from the system.

Does that help clarify some of your questions?

This has been a very interesting thread to say the least. LOL But informative as well.

For my tanks, I never clean the sandbed. I may on ocassion lightly swoop over the surface but thats about it. I mostly have DSB's in my tanks as well. I have found that with my circulation of water I dont often have much if anything to vacuum up.

If your vacuum thing into the sand arent you releasing all the nasty gunk that is built up in there? Like nitrates for instance? I also dont have any sand sifting stars so my sandbed is pretty much as it was when i added it.

Just wondering if I am doing the right thing. I also always advise people not to muck around in their sandbeds so I wanna be sure thats correct advice.

Thanks guys for the entertaining read thus far. Feels like I'm in college and have a massive technical reading assignment. LOL

Be very careful with this; do you not have any sand shifting snails or other critters like micro brittle stars or even large detrivourous brittle stars? If your simply establishing and ignoring, you are potentially creating an environment in which the sand can compact and litterly become a nutrient sink as Schisms suggested. Sandbeds must be maintained in order to function, the methodology can be debated, but the maintanence cannot. Failure to maintain the sandbed can result in things like old tank syndrome.

Can't.. Read.. Anymore...

Ugh, this was a lot, but very informative. Obviously there is no direct answer to this subject and as always, there's more than one way to accomplish the same thing. I personally am tired of dealing with a sandbed and will probably do an sps only with no sand next time around.. Just seems a lot easier.

Glad it was informative. In fact lots of people feel that way, and its one of the reasons that BB or barebottom tanks have become so popular. Easy removal of any waste and/or debris prior to chemical breakdown. Unfortunately eliminating inorganic phosphate is not so easy - but we have protein skimmers for that.
 
Wy Renegade said:
I think your issue is perhaps with your perception of concentration levels of phosphate. In order to understand the process you need a little background knowledge, I'm going to assume that you are familiar with the basic concept of diffusion of substances and at least somewhat with concentration gradient? In other words, we all understand that if the aragonite has a lower concentration of phosphate than the surrounding water, the phosphate will tend to move from the aragonite into the surrounding water. This is very similar to condition in which phosphate is found in the soil and is taken up by the root system of plants. In this case however, we are working with not roots, but algae cells either cellular or multicellular. As the organisms binds phosphate within its cells to form organic compounds the concentration gradiant becomes different then the surrounding water and therefore phosphate moves from the water into the cells. This creates a microenvironment around the cells in which the concentration gradient in the surrounding water is lower than the concentration bound into the aragonite, and thus allows the phosphate to move from the aragonite back into the surrounding water. That is a huge oversimplification of something that involves both biological and chemical processes, but conveys the general idea.

Additionally I'm not sure that your quite getting the concept of removal of phosphates from my perspective. You're focuses on preremoval via mechanical means (i.e. siphoning). I also focus on preremoval however my means are biological rather than mechanical, although like you I also rely on the protein skimmer to remove biophosphate. Once phosphate is introduced, lets say via feeding, you siphon off the excess or left over decaying food. I allow other organisms both macro and microfauna to consume those left over substances. I suppose that I also should point out that I typically have systems that have a very light bioload from a fish perspective, but it is the same principle that is applied in the large aquarium tanks in public aquariums. Nobody goes in and siphons those tanks, they relie heavily on mechanical removal via protein skimming and biological removal via fauna. Once consumed (assuming that you are not overfeeding) these phosphates become bound up as biophosphate which your skimmer will remove. Inorganic phosphates are absorbed and bound by the biological process of photosynthesis. Once phosphates are bound within the organic tissue, removal of that organic tissue (algae harvesting) results in the removal of that phosphate material from the system.

Does that help clarify some of your questions?

That is nearly a crystal clear explanation and thank you. I do see now where this is coming from.

I think the debate for me is 'if' the method you describe has been proven to 'export' phosphate long term via skimming and algae harvesting faster than the 'import' of phosphate long term in a closed system. I can't answer this question through anything ive read or experienced, so i choose to remain proactive when it comes or removal organic matter.

I do see exactly where you are coming from now, just unsure of the actual research that suggests export via the described methods is greater than import, which in a closed system is pretty important.

Also would you happen to have any information on what happens to heavy metals in a DSB setup as you describe? Just curious here. And thanks agains :)
 
Wy Renegade said:
In order to understand the process you need a little background knowledge, I'm going to assume that you are familiar with the basic concept of diffusion of substances and at least somewhat with concentration gradient? In other words, we all understand that if the aragonite has a lower concentration of phosphate than the surrounding water, the phosphate will tend to move from the aragonite into the surrounding water.

It's elementary my dear (in a British accent).. Well actually 10th grade bio. So, maybe a stupid question, but, if aragonite sand naturally has phosphates in it, and the sand comes from the oceans, why do we get the algae in our tanks from it? Is it another there's much more water in the ocean compared to our tanks, so it dilutes it type of deal?
 
My tanks been running 1.5 years and I've NEVER vacumed the sand, should I start? Will it release all sorts of crap and I'm gonna run into trouble or if I take it slow, a bit each water change will it be ok? My sand looks spotless so I don't know if I really need too...
 
That is nearly a crystal clear explanation and thank you. I do see now where this is coming from.

I think the debate for me is 'if' the method you describe has been proven to 'export' phosphate long term via skimming and algae harvesting faster than the 'import' of phosphate long term in a closed system. I can't answer this question through anything ive read or experienced, so i choose to remain proactive when it comes or removal organic matter.

I do see exactly where you are coming from now, just unsure of the actual research that suggests export via the described methods is greater than import, which in a closed system is pretty important.

Also would you happen to have any information on what happens to heavy metals in a DSB setup as you describe? Just curious here. And thanks agains :)

Like most things in the hobby, actual research for anything aquarium based is very difficult to find, as researchers seldom spend any time doing aquarium-based research. Most often the research we find is based in ocean or freshwater systems and happens to be somewhat applicable to the aquarium, such as in the two phosphate research articles we've already posted. So in regards to this, the best I can give you is antecdotal evidence in the form of the long term success of many people who do not siphon aquariums and the obvious success of large scale public aquariums where siphoning also does not occur (certainly this is not a perfect example as many public aquariums actually are able to use ocean water as their source, which obviously begs the question). Some public aquariums however do not have access to that resource and thus are forced to rely on more traditional methods of water filtration. The Denver Marine Aquarium for example relies on water changes, massive protein skimmers, and carbon filtratration as well as some macroalgae growth to maintain water quality in their large aquariums. Perhaps the best antecdotal example I can give you in the aquarium world is PaulB and his 40 year old aquarium. Have you every read through any of his threads on RC or R2R? Here's a classic example of an individual who breaks all the rules and yet maintains a successful tank. His system relies on a reverse undergravel filter and an algae trough for nutrient export (can't tell you for sure if he uses a protein skimmer or not). He'll be the first to tell you that he does not have a DSB, his substrate is actually Dolomite (a very hard form of calcium carbonate). Regardless of your opinions of how he does things, its darn hard to argue with 40 years of contineous success, and his threads are always educational and just plain fun to boot.

In regards to the heavy metals, I've never seen any research related info, although I have seen some speculation in regards to accumulation within DSBs in various threads. To me, it makes sense that there would be some accumulation, since we feed foods made from organisms taken for the oceans where such things do accumulate. However the big question/issue would be in regards to trying to quantify the amounts, and trying to clarify some issues in regards toxic levels. It is in my opinion a very grey area that there has been some speculation on, but no hard evidence to my knowledge. I would also think however that accumulation of heavy metals, if it could be proved to be an issue in regards to DSBs, would in turn end up being a potential issue in any type of sandbed. Admittedly heavy metals and there accumulation is something I know very little about.
 
It's elementary my dear (in a British accent).. Well actually 10th grade bio. So, maybe a stupid question, but, if aragonite sand naturally has phosphates in it, and the sand comes from the oceans, why do we get the algae in our tanks from it? Is it another there's much more water in the ocean compared to our tanks, so it dilutes it type of deal?

Not real sure that I understand your question in regards to the algae? Are you saying that the algae in our tanks comes from this bound phosphate or are you trying to say something else?

Generally speaking, the argument you'll most likely hear is the whole dilution one. That said however a little research into the methodology of mining the LS sold in the aquarium trade might change that opinion. Personally I'm not a fan of purchased LS anyway, as generally speaking all it really contains is some bacteria and a lot of decay. I prefer to use freshwater rinsed dry aragonite sand and seed it from another sandbed. Interestingly among those who subscribe full-scale to the phosphate binding, accumulation idea, rinsing sand and LR with a short vinager bath is one of the suggestions for removing the outer portion of the sandgrains or the LR for removal of bound phosphate. If you've ever tried that, its certainly not something I would recommend, I have no idea how you can do it with sand successfully, as aragonite dissolves in vinager solution relatively quickly. Even fairly large pieces of LR will dissolve completely in a 24 hour period.
 
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Wy Renegade said:
Like most things in the hobby, actual research for anything aquarium based is very difficult to find, as researchers seldom spend any time doing aquarium-based research. Most often the research we find is based in ocean or freshwater systems and happens to be somewhat applicable to the aquarium, such as in the two phosphate research articles we've already posted. So in regards to this, the best I can give you is antecdotal evidence in the form of the long term success of many people who do not siphon aquariums and the obvious success of large scale public aquariums where siphoning also does not occur (certainly this is not a perfect example as many public aquariums actually are able to use ocean water as their source, which obviously begs the question). Some public aquariums however do not have access to that resource and thus are forced to rely on more traditional methods of water filtration. The Denver Marine Aquarium for example relies on water changes, massive protein skimmers, and carbon filtratration as well as some macroalgae growth to maintain water quality in their large aquariums. Perhaps the best antecdotal example I can give you in the aquarium world is PaulB and his 40 year old aquarium. Have you every read through any of his threads on RC or R2R? Here's a classic example of an individual who breaks all the rules and yet maintains a successful tank. His system relies on a reverse undergravel filter and an algae trough for nutrient export (can't tell you for sure if he uses a protein skimmer or not). He'll be the first to tell you that he does not have a DSB, his substrate is actually Dolomite (a very hard form of calcium carbonate). Regardless of your opinions of how he does things, its darn hard to argue with 40 years of contineous success, and his threads are always educational and just plain fun to boot.

Yes i have seen his tank and all i can say is WOW of course as should anyone, however im not even sure he could say for sure how its made it 40 years lol. But it is very impressive.

I do think however that anyone attempting the method of phosphate control as you propose should be aware that its based on a large skimmer and macro algaes both of which need to be optimally operating. Its a method that relies on optimal setup. Results from tank to tank will vary. I think this is probably why you said many DSB's fail due to improper setup. Something i dont think many people take into account when setting up a DSB

Wy Renegade said:
In regards to the heavy metals, I've never seen any research related info, although I have seen some speculation in regards to accumulation within DSBs in various threads. To me, it makes sense that there would be some accumulation, since we feed foods made from organisms taken for the oceans where such things do accumulate. However the big question/issue would be in regards to trying to quantify the amounts, and trying to clarify some issues in regards toxic levels. It is in my opinion a very grey area that there has been some speculation on, but no hard evidence to my knowledge. I would also think however that accumulation of heavy metals, if it could be proved to be an issue in regards to DSBs, would in turn end up being a potential issue in any type of sandbed. Admittedly heavy metals and there accumulation is something I know very little about.

Ok thank you, i didnt think there was much in the way of research on the subject, but thanks.
 
Yes i have seen his tank and all i can say is WOW of course as should anyone, however im not even sure he could say for sure how its made it 40 years lol. But it is very impressive.

I do think however that anyone attempting the method of phosphate control as you propose should be aware that its based on a large skimmer and macro algaes both of which need to be optimally operating. Its a method that relies on optimal setup. Results from tank to tank will vary. I think this is probably why you said many DSB's fail due to improper setup. Something i dont think many people take into account when setting up a DSB



Ok thank you, i didnt think there was much in the way of research on the subject, but thanks.

Indeed.

Absolutely! It also requires, as I've pointed out several times throughout the thread, the maintainance of a fully functioning sandbed and full compliment of the macro and microfauna required to keep it functioning. It is in no way, shape, or form a simple create it and forget it methodology. In many ways, it is probably just as time intensive as yours, but is in my opinion just a more natural way of accomplishing the same result. You might get some purists who would want to argue that, but I'm not one. I believe is using whatever methods are time proven by you to work for you. For myself, I've found this to be a large combination of methods. I've even used the siphon on occassions, just not on a regular basis ;).

In regards to the comment on DSB failure do to improper set-up, I've found that many people in establishing a DSB don't bother to research or learn enough in regards to the proper way to set one up. They simply hear about this idea, go out and buy a bunch of the same-sized sand and dump it into the tank to the desired depth and then expect it to function. A properly set-up DSB requires three layers of sand grains of different sizes, with the most course or plenum being on the bottom, the medium in the middle and the fine on top. While there is some evidence that similar-sized sandgrains may work, to my knowledge its never been researched like the original method (albiet in a somewhat biased manner). Additionally many people never really bother to learn about proper depth, they place sand to a depth that looks nice to them. Few are aware that the depth of 2" to 3 1/2" for example are extremely high risk, as they are neither deep enough for a true DSB or shallow enough for a SSB. Risk of accumulation and release of toxic gases in these sandbeds is much higher than in a properly established DSB. Its a unfortunate case of failure before the system ever started. Then people blame the crash on the DSB, in reality its a failure of the individual rather than the method. But that my friend is an entirely different topic.
 
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