Siphon Your Sand Bed!!

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Wy Renegade said:
Nice clarification, but not the way your initial post reads in regards to "feeding." So just for clarification, you maintained this same star in your tank with weekly siphonings for that entire four year period?

Sorry for not being more clear. But yes same star. Weekly or biweekly siphoning. Also this star has been in 2 different tanks in the past 4 years.

Wy Renegade said:
In regards to the microfauna, that statement is completely accurate. If you allow the debris from your weekly siphonings to settle and looked through it closely with a microscope or even a very good magnifying glass, you are going to find all kinds of microfauna within that water; from micro brittlestars to bacteria. Those organisms live within the sandbed in the water and on the sandgrains and when you remove that water and sandgrains by siphoning you do in fact reduce or deplete the microfauna by default. I'm correct in that they fail in the majority of aquariums, do they fail in all no. As I stated, they are always going to be exceptions to the rule, but encouraging those who do not understand how to properly maintain these animals to keep them is a huge error in my opinion. And simply saying proper feeding isn't going to cut it.

Yes fully aware of microfuana. However, siphoning can not deplete the sand bed of microfuana. Put my sand under a microscope and you will see the same microfuana. Ive done this btw. For some reason people tend to think your siphoning all life out of your bed, its impossible to do. They reproduce quickly and not every area of your tank is subject to siphoning, not every grain of sand.

Wy Renegade said:
Clarification, clarification, clarification. No were in your initial posts did you account for any of these clarifications. When posting general broadsweeping statements or threads like "siphoning your sandbed" proper clarification is needed if your intent is to educate. Someone who doesn't know any better and simply read your post and then went out and started completely vaccuming their entire DSB every week is destined for failure no?

This thread was not directly aimed at DSB's. Failure? No. But your right i should have clarified. My apologies.

Wy Renegade said:
The simple fact is, no sandbed processes phosphates, and you can't claim to be processing your sandbed clean enough on a weekly basis to remove all phosphate and yet leave enough nutrients behind to support the microfauna required to support that sand-sifting star. The two points are counter intuitive. If in fact enough phosphates (i.e. nutrients) are being left behind to support the microfauna, then there are enough phosphates being left behind to bind up in the sand and liverock.

Correct, no sand bed processes phosphates. You can not possibly remove all phosphate from a tank. And your do not need to or would you want to, phosphorus is required for life. Its also being produced on a constant basis. Microfuana can not starve itself out from lack of phosphate because its simple not possible.

Also phosphate only bind to sand and rock in quite excessive amounts. This is what causes many DSB's to crash. DSB's can be very misleading and most dont understand how to take care of them.

http://www.advancedaquarist.com/2002/9/chemistry

Wy Renegade said:
Again, good clarification, but need for others to understand your point. However, to say that the effect is null is completely inaccurate. The fact is that siphoning of that portion of the sandbed depletes the microfauna severely and it has to reseed from the unsiphoned half of the sandbed. This is in fact why only once or twice a year siphonings are recommended no?

No. yes it will rid of a small amount of microfuana. The problem with a complete siphoning often is the disturbance of the anaerobic and anoxic zones preventing denitrification. These zones must be low and devoid of oxygen.

Wy Renegade said:
In regards to the three zones, can you please clarify your position on this. Anoxic by definition means without oxygen, the same as anaerobic, so I'm curious to see on what basis you are trying to seperate the oxygen depleted layer into two seperate layers.

anaerobic is low oxygen. It is impossible to go from oxygen to no oxygen. Anaerobic is the in-between.

Wy Renegade said:
True enough, however a DSB can be properly maintained without siphoning. It can be done with the regular reintroduction of the proper microfauna which burrows and tunnels its way through the DSB maintaining the functionality of the DSB by doing so. That is not maintainance free. You are quite correct in your assertion that a DSB needs to be maintained. However you are incorrect in that the only way to do so properly is by siphoning. There is always more than one way to do things properly in this hobby.

False, again microfuana do not process phosphates. I do agree there is more than one way of doing things properly. However the phosphate issue of not siphoning hasnt been addressed.

Excessive phosphate will result in the binding to sand and live rock and also will only be solvable with the entire sand bed being replaced.

Wy Renegade said:
Actually some recent research would tend to disagree with you. Some studies I've seen indicate that phosphate binds into the sand and LR even with a properly maintained aquarium and sandbed. I fully understand why phosphate is not a problem with a properly maintained fully funtioning system. I believe that part of our differences here is in term of how you and I are defining maintained. You appear to be trying to assert that there is only one proper way to maintain a sandbed and I am simply disagreeing with you.

Disagreement is fine, and i dont mind discussion. I would like to know how you properly maintain a DSB then. Wondering where your phosphate is going then.

Wy Renegade said:
I never proposed any such thing. I proposed the addition of a source of algae as a solution to the removal of phosphates. Which without the actual removal of that algae from time to time is also not effective, as algae binds but does not remove phosphates. I'm not proposing a left along DSB at all, I'm simply stating that a DSB can properly be maintained without siphoning..

If by algae you are referring to Macro algaes in a refugium then yes they will 'help' remove phosphate but in no way do they remove it from a DSB. These anoxic zones are free from oxygen, a refugium will only slowly deal with free floating inorganic orthophosphate. However they do nothing for Organic phosphates trapped in the sand bed.

Also would you not agree siphoning to be the simplest, economical and most proficient way of removing all forms of phosphates and organic matter from a system/sand bed.

A DSB was originally contrived to be a fix or system of dealing with nitrate removal. Adding an algae tank to deal with the DSB sound like your fixing fixes now, instead of the problem? Agree?
 
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Fishfighter said:
All I got out of it was blah, blah, blah, and more blah! Did you guys have your dictionaries out or what?! If your sandbed Is dirty clean it. How's that for clarification? Not trying to be a smarta@* or anything but that was hilarious.

Great place to learn something. And for many people "its dirty, clean it" is not a simple answer lol. Ive seen these discussions get way more elaborate than this.
 
Read every bit and yes did learn a thing or two. Just felt a little tension in the air. Nothing like a good laugh to lighten people up
 
Fishfighter said:
Read every bit and yes did learn a thing or two. Just felt a little tension in the air. Nothing like a good laugh to lighten people up

No tension here, i could talk about these things forever if i had the time. Different opinions and experiences are great, it what makes people learn and what makes you really think.

Being proven wrong means i learn something new. Never a bad thing, and that goes for anyone. No tank is the same and many topics like this can be dependent on routine and setup, often very opinionated.

Ive never been a DSB hater and ive maintained a couple DSB's. They are a method of filtration, and as most know, all filters need cleaned.
 
Ok, is 2" considered a deep sand bed? Because that's what I have and I don't mess with it. I thought I was supposed to leave it alone. How do you siphon a sand bed? Or how do you maintain it.
 
FlopNewsom said:
Ok, is 2" considered a deep sand bed? Because that's what I have and I don't mess with it. I thought I was supposed to leave it alone. How do you siphon a sand bed? Or how do you maintain it.

No 2" is not a deep sand bed. Siphoning a sand bed requires a "gravel vac" purchased at any fish store. The size of siphon and tubing you need depend on grain size of your sand. Smaller grain, smaller tubing.

With fine grain sand, i recommend a longer siphon tube with about a 3/8" hose. Bury the siphon into the sand and allow it to suck up the sand to the top of the tube. When it gets to the top pinch the line and the sand will fall and tumble. This will break up the sand particles an free detritus. As its falling apply and release flow by pinching the tubing to allowing you to separate the sand from detritus and allow the sand to fall back down. Its a little difficult to explain but im sure you could find a youtube video.

Maybe ill have to make one. Dunno
 
I made a rake out of a plastic coat hanger and hot glue that attaches to siphon so sand don't get all sucked up just the crud (AKA POO) looks kind of like this
the red under siphon is a void between rake and siphon to keep from sucking up all the sand
works great

my art skills are lacking a bit but you'll get idea(y)
 
54seaweed said:
I made a rake out of a plastic coat hanger and hot glue that attaches to siphon so sand don't get all sucked up just the crud (AKA POO) looks kind of like this
the red under siphon is a void between rake and siphon
works great

my art skills are lacking a bit but you'll get idea(y)

Amazing idea! However im unsure of putting anything with hot glue on it in a reef tank. I may just try gel super glue, and see how it works.
 
Sorry for not clarifying, I just always have the time to write long posts and explanations like these and i try to keep it basic, but this is far from a basic subject. Ill respond when i get a chance to sit down.

Not a problem. Educated debate is great for the learning process, and as you pointed out, this is hardly a basic topic. Sorry for the delay in my response, but I was on the road this evening, so was unable to follow the thread.

All I got out of it was blah, blah, blah, and more blah! Did you guys have your dictionaries out or what?! If your sandbed Is dirty clean it. How's that for clarification? Not trying to be a smarta@* or anything but that was hilarious.

Sorry about that, stick around and do some research and a few of those blahs may start taking on some meaning. After all isn't that what the boards are all about? Providing an opportunity for all of us to learn and discuss?
 
Sorry for not being more clear. But yes same star. Weekly or biweekly siphoning. Also this star has been in 2 different tanks in the past 4 years.

Nice, always good to encounter the exceptions to the general rule. Not a problem on the clarity, I was simply asking for the clarification for my own knowledge. Do you mind sharing the size of both tanks?

Yes fully aware of microfuana. However, siphoning can not deplete the sand bed of microfuana. Put my sand under a microscope and you will see the same microfuana. Ive done this btw. For some reason people tend to think your siphoning all life out of your bed, its impossible to do. They reproduce quickly and not every area of your tank is subject to siphoning, not every grain of sand.

Perhaps we are arguing over semantics here. for the sake of clarification, to deplete simply means to reduce. So I have to disagree with you here; the fact is you cannot remove some of the microfauna and very fine sandgrains which are removed by siphoning and not deplete or reduce your microfauna. I never suggested that you would or could eliminate all the life from your sandbed. However it is depleted.

This thread was not directly aimed at DSB's. Failure? No. But your right i should have clarified. My apologies.

Absolutely I agree, it is certainly not a failure, nor was it obviously aimed at DSBs, but you also did not exclude them from the discussion no?

Correct, no sand bed processes phosphates. You can not possibly remove all phosphate from a tank. And your do not need to or would you want to, phosphorus is required for life. Its also being produced on a constant basis. Microfuana can not starve itself out from lack of phosphate because its simple not possible.

Also phosphate only bind to sand and rock in quite excessive amounts. This is what causes many DSB's to crash. DSB's can be very misleading and most dont understand how to take care of them.

http://www.advancedaquarist.com/2002/9/chemistry

Thanks for the link, I've read the article. On this point, we may have to agree to disagree. I've been involved in this particular debate a few times over the years, and to date I've seen no clarification of what constitutes high vs. low levels or antecdotal evidence that phosphate it only bound under high concentrations I've wondered if it some of it doesn't come from misinterpreting this article. The article states;

Likewise, phosphate can precipitate onto the surface of calcium carbonate, such as onto live rock and sand. The absorption of phosphate from seawater onto aragonite is pH dependent, with the maximum binding taking place around pH 8.4 and with less binding at lower and higher pH values. If the calcium carbonate crystal is static (not growing), then this process is reversible, and the aragonite can act as a reservoir for phosphate. This reservoir can make it difficult to completely remove excess phosphate from a tank that has experienced very high phosphate levels, and may permit algae to continue to thrive despite cutting off all external phosphate sources. In such cases, removal of the substrate may even be required.

This indicates that absorption of phosphate onto aragonite (i.e. sand or LR) is pH dependent, not phosphate level dependent. The portion that refers to exposure to very high phosphate levels is simply indicating that such phosphate levels in sand or LR is high enough that one cannot deplete it by ordinary means. If you have some other source that indicates phosphate binding by aragonite only occurs under high concentrations of phosphate I'd definitely be curious to see it.

http://www.aoml.noaa.gov/flbay/millero1.html

http://www.fishchannel.com/saltwater-aquariums/aquarium-frontiers/what-is-phosphate.aspx
(also written by Randy Holmes-Farley and similar to the previous article, but with a bit more clarification on inorganic and organic phophates).

http://yyy.rsmas.miami.edu/groups/jmc/fla-bay/fbay.html
(Older research than the first link, but interesting non-the-less)

I do agree that many people do not truly understand how to properly care for or maintain a DSB, but would argue that the three reasons I previously presented are far more common failure issues than maintaince. Many people think if they simply pile sand 6" deep into an aquarium they've created a proper DSB, then they wonder why it doesn't work like it is supposed. In regards to phosphate being the culprit in a crashing DSB, I'm wondering if you're mixing your chemicals? Generally high nitrate levels are the considered to be the main culprite in a crashing DSB.

No. yes it will rid of a small amount of microfuana. The problem with a complete siphoning often is the disturbance of the anaerobic and anoxic zones preventing denitrification. These zones must be low and devoid of oxygen.

Again, I have to disagree. If your meander your way through the thread on DSB that exists on the same site you pulled the article from, you will notice that in those cases were siphoning of the DSB is recommended in six month intervals, it is to allow the rejuvination of the microfauna in those areas it was depleted (reduced).

anaerobic is low oxygen. It is impossible to go from oxygen to no oxygen. Anaerobic is the in-between.

I'm sorry, but you are incorrect. A quick google search on your part will quickly reveal that you are using the terminology incorrectly here. The terms that I believe you are looking for are oxic (containing oxygen), hypoxic (containing insufficient oxygen) and anoxic (without oxygen). The terms anoxic and anaerobic are synonyms and imply the same condition (devoid of oxygen)

False, again microfuana do not process phosphates. I do agree there is more than one way of doing things properly. However the phosphate issue of not siphoning hasnt been addressed.?

Sorry, I have to disagree again, from the article you referenced . . .
<H2>How to Export Phosphate
So now that we know where phosphate comes from, and how much, we can proceed to ask where it goes and how to maximize those export processes. Certainly, some phosphorus goes into the bodies of growing organisms, including bacteria, algae, corals, and fish. Some of these organisms stay permanently in the tank, and others may be removed by harvesting of algae, skimming of small organisms, and even pruning of corals.
</H2>certainly bacteria are considered part of the microfauna.

Schism;2029369Excessive phosphate will result in the binding to sand and live rock and also will only be solvable with the entire sand bed being replaced.[/QUOTE said:
Only excess phosphates continually exposed over a long period of time;

from the article

If the calcium carbonate crystal is static (not growing), then this process is reversible, and the aragonite can act as a reservoir for phosphate. This reservoir can make it difficult to completely remove excess phosphate from a tank that has experienced very high phosphate levels, and may permit algae to continue to thrive despite cutting off all external phosphate sources. In such cases, removal of the substrate may even be required.

As indicated by the article, the binding process is reversable and if exposure is only short term, most of that phosphate will be eliminated by the simple reversal of that process. Removal of the substrate is only required in event of inordantaly high levels of phosphate bound into the aragonite.

Disagreement is fine, and i dont mind discussion. I would like to know how you properly maintain a DSB then. Wondering where your phosphate is going then.

I thought I had clearly stated this several times. Proper maintance of a DSB can be accomplished by maintaining a complex and diverse population of both macro and microfauna which is responsible for maintaining the DSB. In other words, the same way Mother Nature is doing it. In regards to where my phosphate is going, I'm relying on two of the top methods indicated by Mr. Holmes-Farley in his article; macroalgae growth and harvesting and skimming. You will notice that Mr. Holmes-Farley does not advocate siphoning as an effective method for phophate removal (for reasons we will explore here in just a bit).

If by algae you are referring to Macro algaes in a refugium then yes they will 'help' remove phosphate but in no way do they remove it from a DSB. These anoxic zones are free from oxygen, a refugium will only slowly deal with free floating inorganic orthophosphate. However they do nothing for Organic phosphates trapped in the sand bed.

Rather confused by this? Organic substances are not going to be found in the lower regions of a DSB except in the cases of those that are bound up within the living organisms (bacteria) that are found there. organic phosphate is constantly being consumed within the sandbed by the microfauna and microflora that exists there. It does not become trapped forever within the sandbed, organic processes as well as chemical converstion into inorganic phosphates effectively remove it from the sandbed on a regular basis. Movement of water (and the substances dissolved in it) into the DSB is not a one way street, if it where, all your water would eventually sink into the DSB.

Also would you not agree siphoning to be the simplest, economical and most proficient way of removing all forms of phosphates and organic matter from a system/sand bed.

No, I'm sorry, but I disagree. In truth siphoning is a very ineffective way to remove phosphate. In fact you will notice that Randy Holmes-Farley does not even recommend it as a method for doing so. What siphoning does is remove dead organic material and debris and it is very effective at doing so. This will certainly help with the elimination of organic phophate which is bound up within that organic mater and debris, but does very little for the effective removal of inorganic phosphates unless massive quantities of water are being removed and replaced with phophate free water.

A DSB was originally contrived to be a fix or system of dealing with nitrate removal. Adding an algae tank to deal with the DSB sound like your fixing fixes now, instead of the problem? Agree?

LOL, nice try. If in fact a system could only be kept phosphate and nitrate free by simple siphoning. unfortunately, because both substances are contained in the living organisms within your reef, as well as many of the substances you add to the reef, siphoning, even on a weekly basis will not eliminate either of these two substances as they are constantly being released into the water column by the processes of life. If it was a simple as you propose, there would be no need of phosphate binders, refugiums, skimmer or any of the numerous other items which appear so commonly within this hobby.
 
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Great place to learn something. And for many people "its dirty, clean it" is not a simple answer lol. Ive seen these discussions get way more elaborate than this.

Indeed they do, and they are always best when one can keep them objective and without emotion. It allows us to learn from each other, rather than becoming bond up in our own opinion.

Read every bit and yes did learn a thing or two. Just felt a little tension in the air. Nothing like a good laugh to lighten people up

No tension on my part. I love being involved in these type of discussions, I think it is where we truly learn and we all have the ability to broaden our understanding.

No tension here, i could talk about these things forever if i had the time. Different opinions and experiences are great, it what makes people learn and what makes you really think.

Being proven wrong means i learn something new. Never a bad thing, and that goes for anyone. No tank is the same and many topics like this can be dependent on routine and setup, often very opinionated.

Ive never been a DSB hater and ive maintained a couple DSB's. They are a method of filtration, and as most know, all filters need cleaned.

Right on! For what it is worth, I'm certainly not a hater of the siphon method. Personally I think this is one of the major misconceptions of the hobby on the freshwater side where they frequently state that debris doesn't sink into the sandbed. Anyone who has every maintained a sandbed on the salty side can easily see the errors in this logic.

I read every single post. All I can say is........ +1 schism!!!!!

Stick around youngster and you may actually learn a little something from an old foggy.

Ok, is 2" considered a deep sand bed? Because that's what I have and I don't mess with it. I thought I was supposed to leave it alone. How do you siphon a sand bed? Or how do you maintain it.

Agree with almost all of Schisms info below. It is not a DSB and you do need to maintain it. The only part I'm not sure I agree with totally is in regards to siphon and hose size in relation to sandgrain size. I'd like to see that clarified a bit more. Personally I like to base siphone size on the size of the aquarium and volume of area I'm trying to clean and hose size is typically dictated by the siphon you purchase.

No 2" is not a deep sand bed. Siphoning a sand bed requires a "gravel vac" purchased at any fish store. The size of siphon and tubing you need depend on grain size of your sand. Smaller grain, smaller tubing.

With fine grain sand, i recommend a longer siphon tube with about a 3/8" hose. Bury the siphon into the sand and allow it to suck up the sand to the top of the tube. When it gets to the top pinch the line and the sand will fall and tumble. This will break up the sand particles an free detritus. As its falling apply and release flow by pinching the tubing to allowing you to separate the sand from detritus and allow the sand to fall back down. Its a little difficult to explain but im sure you could find a youtube video.

Maybe ill have to make one. Dunno

Regardless of your efforts, not all sand will fall back. Very small grains of sand suspended in the water are always removed when you siphone.

I made a rake out of a plastic coat hanger and hot glue that attaches to siphon so sand don't get all sucked up just the crud (AKA POO) looks kind of like this
the red under siphon is a void between rake and siphon to keep from sucking up all the sand
works great

my art skills are lacking a bit but you'll get idea(y)

See the above, but good idea for releasing the larger organic debris into the water column.
 
Renegade, i completely thank you for making my mind hurt tonight from reading and quotation marks lol. Im going to respond tom probably with a all encompassing response as i cannot do that many quotes without my brain hurting badly, especially on my phone lol.
 
Ok here we go lol.

Phosphate and sand:

Yes, phosphate will bind to sand/aragonite. Binding is however not a source of removal in an aquarium and sand does not bind an infinite number of phosphate molecules. Sand has a limit, once this limit is reached the sand bed must be replaced.

Replacement of the sand is your export of phosphate. It is the only way to get rid of all that bound phosphate, just like macro algae it must be harvested. However, in a DSB having to remove the entire substrate and replacing it can and will have a huge impact on the tank, not to mention 'microfuana'. This is the drawback to a DSB that is not cleaned and maintained. There is no way around this fact and its barely touch upon by the author. The long term implications are large. Short term yes phosphate will be 'controlled' if thats why you wish to call it.

Microfuana and phosphate:

All life requires phosphorus to live and grow. Microfauna will take up some phosphorus through food intake and convert it to growth. The percentage used is small, the unused percentage is excreted as waste (phosphorus).

In no way do these organisms process phosphates, they just require a small amount to live, like everything else. Also note that the used phosphorus is never removed or broken down, when the organism dies, the phosphorus is release back into the water column. In no way is this removal.

Siphoning and Microfuana/microflora:

Does siphoning remove microfuana? Absolutely. Is the effect if done properly minimal? Yes. Obviously the less sand you siphon out the more minuscule the impact. The largest impact comes from the smallest particles of sand being siphoned out as a result. Well what is contained in this sand 'dust'? The answer is phosphates. We already established phosphates bind to sand.

What does this mean for the microfauna? Some are removed, the small amount contained in the very small amount of sand siphoned of. The lost organisms are quickly replenished from the existing sand bed. And in no way hinder denitrification. Bacteria (microflora) are dependant on food availability (bioload) and reproduce rapidly. Denitrification is dependent on anaerobic bacteria and absence of oxygen.

Microfuana are beneficial organisms that feed on detritus and other microfuana organism. They are important to a balanced ecosystem. Siphoning can not and will not wipe these organisms out. And besides being food for other organisms they gave no duty other than the further break down, transfer, and the distribution of waste across multiple layers of a sand bed.

Siphoning and DSB's:

Siphoning will not and can not destroy a deep sand bed. It will reduce numbers of microflora/microfuana however step can be taken and a maintenance routine devised that can completely negate any harm done by siphoning. This routine has already been discussed and personally i think its playing it way way on the safe side of harming anything.

By siphoning the aerobic zone you are limiting the amount if nutrients that need to go through denitrification and also limiting the phosphate that essentially becomes bound in the sand. This means a better serving and longer lasting sand bed.

---------------------------

Im sure i missed points but im tired lol. Oh and as far as why i suggest a smaller siphon depending on grain size. It is because it is easier to control the flow and uptake of sand with a smaller tube. Especially with fine grain sand.

Pinching off a 1" siphon hose for example is not very easy. The lighter the sand the lower the flow you want. Suck the sand, pinch the hose and pull end of siphon up out of sand. The sand will tumble. Release again for a second and detritus will flush free. Allow the sand to fall while also allowing some flow through periodically unsuring the detritus stays suspended and siphoned out of the tank. Complicated to explain kinda without seeing it lol.
 
Hey guys I always have been confused on this topic . My bed is 6 inches and I just stick the vac about an inch jn the sand and vac away. Is this the right way to maintain it? I'll be honest after reading this thread I don't know what I should be doing.
 
Hey guys I always have been confused on this topic . My bed is 6 inches and I just stick the vac about an inch jn the sand and vac away. Is this the right way to maintain it? I'll be honest after reading this thread I don't know what I should be doing.

Understandably! I think that both Schism and I will agree that mainanence of the sandbed is absolutely required. We may disgree on the most effective methodology for doing so. In regards to your question, yes the method you are describing will effective help in maintaining your system. Will it eliminate the phosphates from your system is a completely different question and the answer is no. Will it help to keep them at acceptable levels, the answer is yes. Clear as mud?
 
Clear as mud lol yea that pretty much sums it up for me. I just get worried about how people say they crash a tank and since I have no cuc I just want to make sure . Thanks
 
Well you did better than I might have at that particular time of the morning. Sorry to keep breaking down your posts into bite size pieces, but while I can agree overall with what I think is the big picture message you are trying to convey, there are a number of points which I think continue to need clarification.

Ok here we go lol.

Phosphate and sand:

Yes, phosphate will bind to sand/aragonite. Binding is however not a source of removal in an aquarium and sand does not bind an infinite number of phosphate molecules. Sand has a limit, once this limit is reached the sand bed must be replaced.

Agree

Replacement of the sand is your export of phosphate. It is the only way to get rid of all that bound phosphate, just like macro algae it must be harvested. However, in a DSB having to remove the entire substrate and replacing it can and will have a huge impact on the tank, not to mention 'microfuana'. This is the drawback to a DSB that is not cleaned and maintained. There is no way around this fact and its barely touch upon by the author. The long term implications are large. Short term yes phosphate will be 'controlled' if thats why you wish to call it.

Not sure that you're addressing this at me specifically, but want to address it regardless. First off, for clarification, replacement of sand is not my personal method for removing phosphate, nor is it in my opinion either an effective or economical method over the long term of a tank. Again from the article, the most effective methods for phosphate elimination are . . .

Here is a list of ways that people can reduce phosphate levels. They are listed in order of preference that I have for addressing these issues in my own system:
  1. The big winner is macroalgae growth. Not only does it do a good job of reducing phosphate levels, but it reduces other nutrients as well (e.g., nitrogen compounds). It is also inexpensive and may benefit the tank in other ways, such as a haven for the growth of small life forms that help feed and diversify the tank. It is also fun to watch. I’d also include in this category the growth of any organism that you routinely harvest, whether corals or something else.
  2. Skimming is another big winner, in my opinion. Not only does it reduce organic forms of phosphate, but it reduces other nutrients and increases gas exchange. Gas exchange is an issue that many people don’t recognize, but that can contribute to pH problems.
  3. The use of limewater, and possibly other high pH alkalinity supplements, is also a good choice. It can be very inexpensive, and it solves two other big issues for reef keepers: maintaining calcium and alkalinity.
  4. Commercial phosphate binding agents clearly are effective.
  5. Simply keeping the pH high in a reef tank (8.4) may help keep phosphate that binds to rock and sand from reentering the water column. Allowing the pH to drop into the 7’s, especially if it drops low enough to dissolve some of the aragonite, may serve to deliver phosphate to the water column. In such systems (typically those with carbon dioxide reactors), raising the pH may help control soluble phosphate.
The first two listed are IMO the simplist and most effective methods for phosphate removal.

Microfuana and phosphate:

All life requires phosphorus to live and grow. Microfauna will take up some phosphorus through food intake and convert it to growth. The percentage used is small, the unused percentage is excreted as waste (phosphorus).

Agree, but disagree. the far more common form for excreted phosphorus is organic phosphates.

In no way do these organisms process phosphates, they just require a small amount to live, like everything else. Also note that the used phosphorus is never removed or broken down, when the organism dies, the phosphorus is release back into the water column. In no way is this removal.

Have to disagree here. First off for points of clarification, phosphorous is a chemical element, the same as carbon, nitrogen, and oxygen. Phosphorous is of course the building block of phosphate, the chemical molecule in debate. No living organism (to our current knowledge) has the ability to create or destroy any of these elements. What all living organisms do do is processes these elemements on a continual basis through biological and chemical processes that cause them to be bound up into organic compounds such as DNA and proteins or eliminated from the same. By definition, all living organisms are involved in processing these elements on a continual basis. Once they have bound up into organic molecules, these compounds are effectively removed from the system over the short term. They can be returned as a result of waste elimination or death and decay in one form or another. So it is removal for the short term, but not the long term. Long term removal requires either removing the living organisms (done effectively through the removal of bacteria (microalgaes) or macroalgae)) or mechanical removal of organic phosphates (done effectively by protein skimming).

Siphoning and Microfuana/microflora:

Does siphoning remove microfuana? Absolutely. Is the effect if done properly minimal? Yes. Obviously the less sand you siphon out the more minuscule the impact. The largest impact comes from the smallest particles of sand being siphoned out as a result. Well what is contained in this sand 'dust'? The answer is phosphates. We already established phosphates bind to sand.

What does this mean for the microfauna? Some are removed, the small amount contained in the very small amount of sand siphoned of. The lost organisms are quickly replenished from the existing sand bed. And in no way hinder denitrification. Bacteria (microflora) are dependant on food availability (bioload) and reproduce rapidly. Denitrification is dependent on anaerobic bacteria and absence of oxygen.

Agree, although we might debate the term quickly, I don't think we need to do so any further for the sake of the discussion.

Microfuana are beneficial organisms that feed on detritus and other microfuana organism. They are important to a balanced ecosystem. Siphoning can not and will not wipe these organisms out. And besides being food for other organisms they gave no duty other than the further break down, transfer, and the distribution of waste across multiple layers of a sand bed.

Agree, although I still contend that it can effectively reduce numbers significantly over the short term.

Siphoning and DSB's:

Siphoning will not and can not destroy a deep sand bed.

Incorrect siphoning can and will destroy a DSB and the system is supports, especially in the case of a neglected DSB.

It will reduce numbers of microflora/microfuana however step can be taken and a maintenance routine devised that can completely negate any harm done by siphoning. This routine has already been discussed and personally i think its playing it way way on the safe side of harming anything.

By siphoning the aerobic zone you are limiting the amount if nutrients that need to go through denitrification and also limiting the phosphate that essentially becomes bound in the sand. This means a better serving and longer lasting sand bed.

Agree again, although once again, it is not the only effective way to do so.

Im sure i missed points but im tired lol. Oh and as far as why i suggest a smaller siphon depending on grain size. It is because it is easier to control the flow and uptake of sand with a smaller tube. Especially with fine grain sand.

Pinching off a 1" siphon hose for example is not very easy. The lighter the sand the lower the flow you want. Suck the sand, pinch the hose and pull end of siphon up out of sand. The sand will tumble. Release again for a second and detritus will flush free. Allow the sand to fall while also allowing some flow through periodically unsuring the detritus stays suspended and siphoned out of the tank. Complicated to explain kinda without seeing it lol.

I understand the process you are trying to explain here, and you did a fairly good job of explaining it.

So the take home message I think we agree on is that effective and correct siphoning can help to control overall phosphate levels by eliminating many of the potential sources of phosphates (i.e. excess food, debris, and waste), before they can be broken down and become a potential issues. Yes?

It in and of itself however it is not a effective method for the elimination of phosphates, as phosphates are constantly being introduced into our tanks by the organisms that live within it, as well the substances (such as food) that we place in it. Effective reduction of phosphates themselves is accomplished either through growth and elimination of macro and microalgaes or some mechanical means of elimination (skimming or phosphate binding reactions). Certainly the overall size and feeding needs of the aquarium in question also plays a large role in this process. Schism, I notice that you employ a very effective protein skimmer on your reef, and I'm willing to bet that like the rest of us, you remove a cup of that nasty green goo on a regular basis. That is your most effective means of phosphate removal.

Thank you much for the informed debate, I enjoyed it greatly! I look forward to continued opportunities to cross mental swords with you, as that is how we all expand our knowledge. Happy Reefing my friend!
 
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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 ?
 
Ok, I have a 4-5" dsb but my sand is sugar sized grain. How should I clean it? It ALWAYS gets sucked up.
 
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