DSB Maintenance

[justplainfishy]

[charlesr1958]

Thanks for the question, since that is one subject that is near and dear to me.

Assuming the DSB is set up with the proper grain size (sugar grain sized or smaller), and that it came loaded with the microscopic worms, pods, and all the other multitudes of life forms that make live sand alive, then the issue we face per maintenance only involves those life forms.

As with any ecological system, a sandbed has both predators and prey, and as with any small enclosed space, the predators through their feeding and their own reproduction will sooner or later devastate (eat) most all of the prey, leaving the predators to starve to death, which in turn leaves you with a dead sandbed. And a dead deep sandbed can start to turn really nasty. This is exactly why DSBs got a bad reputation, not because they will always be bad, but simply because the hobbyist sets up a dead DSB or allows it to die and is then surprised when it fouls his tank, and instead of blaming himself for not understanding biology, he blames the DSB.

To avoid the eventual shift in predator and prey populations, I have always removed 1/5th of my sandbed and replaced it with new live sand every two months. I do not siphon out just the surface of the entire sandbed, that would be a bad thing to do (biofilm is on surface). Instead, I section my sandbed into five areas and starting at one side of the tank, I siphon out one 1/5th area from top to bottom and replace it with new live sand, then two months later, I move over one area and do it next and so on and so on. Its not that I want or need the new sand grains, its the life that comes with it.

As you can see, such a routine can become a chore as well as an expense for those that must buy their live sand, it is also a waste of sand as well. These are exactly the reasons for why I collected those sandbed synapids and sea cucumbers. Ever since I add three of those synaptids a year ago, I have not changed out any sand. Instead of having or worrying about predator/prey populations, I can sit back and let the synaptids take over the job that the multitudes of microscopic life forms once performed. You will always have some microscopic life, but most likely not in the amounts needed to keep a DSB fully functional. Last month I also added a sandbed sea cucumber to my DSB and it is doing very well also. Last night, by chance, I also saw that I still have a few sea biscuits (sand dwelling sea urchins) in my sandbed as well. Please see my live rock/sand page for more details and links. For photos of the synaptids, sea cucumber and sea biscuits, please see the following pages as well. Thanks.







Chuck

[justplainfishy]

[randell]

[rav888]

Sir charles thanks for all the infos.
Sir, another question about DSB. How would i know if the DSB is already dead or in short its not already doing its purpose. What would be the good signs of having an active DSB aside from the ocean smell of the tank
( not sure though ) ?
Thanks in advance sir.

[CLYVZ]

Wow! another lesson learned! Thanks Chuck!

[charlesr1958]

[rav888]

sir chuck thanks again for the infos.

[jackryan]

Hi Chuck! What would be the tell-tale signs that the DSB is about to "crash" or is no longer beneficial to one's tank set-up?

[charlesr1958]

I suppose I should have said why all of that life in the sand is needed (for a dsb).

A DSB is thought of as a home for anoxic bacterial strains that use nitrate as an energy source, which is why most of us use a DSB. Those same bacteria that work so hard for our systems can also lead to the systems failure due to sandbed clumping. Since the bacteria are not motile, they secrete a substance that binds themselves to the sand grain(s) as well as secreting a exterior covering called a "glycocalyx." It is the glycocalyx that creates the real problems as it can form brick hard clumps that prevent any water movement through the sand bed and allows the formation of a greater amount of sufides. Which is one way to tell that your sandbed has pretty much died. It is all that life through their movement through the sandbed that breaks up the glued sand grains and prevents the clumping. Of course, you would want to know if such clumps are being formed before they kill your tank. So it might be a good idea to poke a finger straight down into the sandbed in various spots once every few months to see if you can feel any clumps. DO NOT do this in young sandbeds! Only after a sandbed is at least six months old is it okay to slightly disturb the sandbed with a few finger pokes into it. Even with established sandbeds, you do not want to poke around so much so that you stir the sandbed, just a few pokes here and there will tell you if the sand grains are still as they should be.

Chuck

[christian]

sir is there any solution to prevent such situation? thank you sir...

[charlesr1958]

Only by keeping the life in the sandbed. Which I detailed above. If I could not keep the life, I would not have a DSB and instead just keep a inch bed.

Chuck

[christian]

[charlesr1958]

When I speak of predators, I not only mean the larger ones such as sand sifting gobys or starfish, but the microscopic predators as well. Just as there are a great many small & microscopic worms that consume the organics in the sandbed, there are also small / microscopic predators that eat the "good" worms. This is why its a good idea to either remove and replace a small section of the sandbed with new live sand every month or two or put some of those synaptids into the sandbed.

A Photo example of a small sandbed predator (A member of the Syllidae worm family)



For more info on sandbeds, as well as more photos of what can be found living in a sandbed, please see my . Thanks.

Chuck

[christian]