Put the gloves on and let's talk DSB.

[mick77]

Head hurts, too much information at once, need coffee. JK Excellent info mojoreef, for an instant I was transported back to Biology class (man I wished I would've let it all sink in more). I'll keep this thread marked to see what all everyone has to say about the controversial DSB. Am I missing something, but don't the tides constantly turn over the sand bed in the ocean? If this works in nature, why couldn't we simply stir our sand on a weekly basis in our own tanks?

[Scooterman]

And I thought My head hurts LOL

[angnak]

Just tagging along.

[Imperial]

uhhh wow that's alot of info.

[mojoreef]

LOL TG TdWyatt is a very good friend and a very smart guy, and has alot of points that do need to be addressed, I have doen it for him befor but for sake of education like do it again.

DSBs DO process Carbon, the DO break it down to its final mineral ash, bacteria do play their role in doing the nitrates and they DO sink a goodly amount of the stuff we don't want in the water column. Heavy feeding will always load the water column with nitrogen, phosphates, DOM as fats, carbohydrates and proteins, and minute particulate materials

Toms overall concept of a DSB is to allow it to be the sink that it is, then simply remove it when it fills. Now this is a viable options for folks that want to do it this way. But I believe if most folks had that knowledge about it they wouldnt pursue it. The carbon Tom refers to is what is use for respiration, as in the energy the critters use in thier daily lives, but it is very insignificant when looking at the whole picture. Bacteria, ligants, chelators will bind metal and other toxins, but they will do that as soon as the hit the water column if they are free ions or loosly bound ions, so it doesnt pertain to the critters in the bed. Although the critters in the bed will also do that but they will physicaly remove it from the sand particles themselves.

There are a large number of heavy metals that chemically bind or are in ionic association with carbonate sediments. All the divalent ions are capable of binding in the place of calcium to the carbonate in the sand bed, some form insoluble bonds, some are in equilibrium with soluble phases of the ionic forms. Phosphate is a good example: It forms a highly insoluble salt with calcium and precipitates out of solution, especially with Kalk additions, effectively removing phosphate as a source for nuisance algal blooms. The sandbed has no export or processing capacity for phosphate, so this substance builds over time, leading to potential mass release during substrate disturbances (like stirring the substrate). The only way of preventing a buildup of phosphate is to find some way of exporting it, either (can't believe I'm saying this) use an algal scrubber and harvest the microalgae, or use a refugium (my preference) and export the macroalgae.

Tom is dead on in this, and this is more important to us as reefers then the build up. it is the conctant algae battles that will discourage us and make us finally give it up or quit. So this is the problem we really need to work on. Phosphates will create a cycle that is hard to break with in the bed. A refugium down the line will not touch what is happening here because the phosphates in the bed are not availble to them and/or locked up prior to getting to them. The cycle is simple, phosphates are added to the tank, lets say through feeding, food and waste hit the bed, bacteria b egin to reduce it algae begins to absorb it, you get a small algae bloom based on the ammount of food available. as food is used up the algae dies off and the bacteria population grows from feeding on the decaying alge, this now runs out and the bacteria die, they decompose and the alge has a new food source. just a simple cycle. You can harvest the cyano or hair and it will be exported but most folks dont like that. Now with continious feeding the cycle gets bigger as more and more food is available, you eventually hit a point of saturations and now your in constant battles. Thier are ways to beet it but we can get back into that later.

Mike

[mojoreef]

Adams post is pretty solid and gives you a good picture.
So lets make this a bit easier to grasp. Exporting is physically removing something from the system. In the case of a DSB because part of the nitrogen cycle is to turn it into gas and the fact that the gas is being release it is an export. So good thing. If you feed a fish a peice of shrimp, it will poop out 90% of that peice of shrimp, thus no export its 10% in the fish and 90% back in play. So the poop hit the bed, the conch or cuke or whatever eats the waste, it in turn poops out 90% and binds 10% this goes right down the food chain including the bacterial processes. Here the problem. If the bacteria, or the snail or the cuke or the conch never dies, or if you physically remove it from the tank, its all good for what they happen to consume. If they die, or go sexual, which they all do (in the case of bacteria by the billions every day) everything they have incorporated is back into play.
We as Humans do the same thing. Adam touch on export in his post animal exportation. Nice idea but a real PITA and not very viable for most. Remeber folks they are cycles not exports. A DSB is a habitat for biochemical cycles not exportation, unless you can figure out how to interupt the cycle and remove something from the game.
The key to making a DSB work is in figuring out how to do it and then being religiuos about doing it.

This can be a very good thread for all of us to learn from, because it is the bases for keeping tanks, and will plly to almost all the things we do to keep our critter happy and healthy.
Please join in. and lets keep this really light

take care

Mike

[tankgirl]

Wonderful reply, Mike!!! Most everything I've learned has either come from you or been clarified by you. Waiting for further clarification...

mick77;

why couldn't we simply stir our sand on a weekly basis in our own tanks?

Mike probably didn't see your post yet. If you stir the sand, you don't have a DSB. Natures DSB is really, really deep, tides don't touch more than the thinnest possible layer at the top. Nature doesn't depend on a bacterial filter for export - she depends on dilution. We can't hope to mimic the kind of water changes Ma Nature uses. If you stir up your DSB, you expose the anaerobic bacteria to oxygen and they no longer function as anaerobic bacteria. The way a DSB works is that, at a certain depth bacteria can't obtain oxygen and so they use something else (I forget what right now, Mike will know) but that process breaks down nitrogenous compounds. If they can get to oxygen, the process no longer works.

[mojoreef]

Mick great thought.

Am I missing something, but don't the tides constantly turn over the sand bed in the ocean? If this works in nature, why couldn't we simply stir our sand on a weekly basis in our own tanks?

See this is the difference in nature. Nature has its ways of fighting build up. Disturbances flush out build up, if its wave actions, tides, storms or what ever. If places dont get this they run into trouble and skew the enviroment to thier likings, such as lagoons, swamps and so on. Now in nature stiring is ok mountain of water mean good dilution and not to many problems. but in our tanks we must be a little more careful, but we can still do it. Manually stiring the sands top layer and syphoning out the build up is EXPORT. We are exporting the build up of all sorts of bad stuff. This will prolong the life of the bed for sure.good thought, now we are working folks, lets get deeper.


Mike

[mojoreef]

TG your right to a point. The bacteria that comsumes nitrate is fuculative, as in it can comsume oxygen and nitrate. When you do a stirring you will loose that ability for a bit, but remember we are talking about a whole lot of bacteria, we created the ultimate enviroment ofr them, fine sand with lots of surface and virtually no flow. So the wait wont be to long and the gain might be worth it.
Your right about mother nature its tough to make the comparison to our tanks and thats what gets alot of folks in trouble. A DSB is a filtration concept using bacteria to cycle detritus, just that nothing more.


mike

[ScottT1980]

I don't have much to add because Mike is pretty much dead on but...

I must say, the problem with an aquarium is that it is a closed system and the problem with a DSB is the need for some sort of exportation (in other words, it can only act as a sink for so long until KABOOM). This need for exportation is always going to be a problem in any closed system and so the problems associated with a DSB should not come as a suprise...

Of course, I see the benefits of a remote DSB but then again, the problem of exportation will still be there, its just that the means to go about that exportation (i.e. dump the DSB and make a new one without disrupting the show tank) is a bit easier. With the remote DSB, I worry about that time-span immediatly following the removal of an old DSB and the addition of a new one. I don't see how this could be a gradual process (the anoxic region will be disrupted, letting out toxins) and so therefore you would have to replace with an entirly new DSB. If you tank is mature, I would think that a new, "unseeded" DSB could recreate the new tank syndrome and potentially prompt headaches. Is this a correct assumption or am I missing something? I mean, I know that the LR in the main system will be loaded with bacteria (aerobes and anaerobes) but I don't know if that will suffice, even temporarily, in a system that was dependent on a "mature" DSB. Again, having not read much on remote DSBs, I am not wholly in the know, just speaking from what my tired brain can come up with at the moment...

As far as exportation goes, I just can't think of any other option other than being proactive and involved with your tank. Obviously though, the easier it is to maintain, the better off the method. I just can't think of any other method that would directly solve the exportation problem (although some appear to make it easier to control than the DSB)...

Did any of that make sense?

Take er easy
Scott T.

Edit: Of course I say closed system without even thinking that the Earth itself is a closed system, now I have confused myself. I know that sulfur is used in many biological processes, especially the formation of proteins, thus rendering it "non-toxic." So exportation is not so much the issue as is rendering these molecules biologically inactive or in a non-toxic form...

[tankgirl]

Hi Mike, somewhere down the line in this thread, I hope we'll also talk about Dr. Ron's current statements that small DSBs can't work. And along with that some info about corners, submerged LR, DSB size and how that affects bacterial populations? I realize I'm jumping the gun but just wanted to get that in the thread before I forget about it, hoping we can cover that, too!!!

[tankgirl]

Scott, good post!!!!

Just want to add, again, according to Dr. Ron, remote DSBs can't work, because they have to be in contact with the nutrients IN the tank and sufficient bacterial populations and diversity can't occur remotely.

[Scooterman]

Originally posted by ScottT1980
I don't have much to add because Mike is pretty much dead on but...

I must say, the problem with an aquarium is that it is a closed system and the problem with a DSB is the need for some sort of exportation (in other words, it can only act as a sink for so long until KABOOM). This need for exportation is always going to be a problem in any closed system and so the problems associated with a DSB should not come as a suprise...

[/i]

You can't expect to duplicate what nature does, instead you have to develop a system that works within our constraints..................Starboard or BB is a good option for
Some but not all, If your willing to support a DSB it can be done successful for quite some time depending on your dedication to good husbandry you can overcome some of the problems but keep in mind it is a box closed in except the top, so what you put in stays in until it is physically removed somehow.

[mojoreef]

Scott made sence to me.

I would like to make this thread a non anti DSB thread, we can start up another thread on different alturnatives of doing things. Alot of folks have DSB's and I think if we have a good conversation we can find ways to make them work a bit or even things for folks to watch out for.

TG Dr. Ron has already addmitted that dsb's dont export and merely act as recycling centers. So lets not bring him into this conversation, he is the one that got us hear in the first place.
I tried the remote DSb also, its pretty much the same thing as ones in the tank, with the exception that you must make sure you gett all the food and waste from the tank into them in order for them to be effective.From thier all the same rules apply. his size comment was basically if you have a 90 gallon tank and a refugium with a remote DSB it must be the same size as the tanks surface in order to be as good as one in the main. This works for some folks who have room, but not for most.


Mike

[EdgeKrusher]

So after reading this, and the info you've given me on cleaning up cyano, I think I understand it better. By stiring up a small portion of the sand bed it breaks up the bonds formed by the phosphate and other nutrients. And by syphoning the water around the area you're disturbing you're effectively exporting the nutrients and toxins? Right, or do I have this all backwards.

Thanks

EK