Limitations of DSB's - Page 11

Spanky · 04-25-2003, 09:55 PM

You know what Tom? you're right. Organics is a big word. I guess we're talking about mostly poop here.

Probably the biggest indicator of elevated organics would be nitrate readings, phosphates, and hair algae.

Tom Hulse · 04-26-2003, 12:34 AM

"we're talking about mostly poop here."
That's mostly nitrogenous waste, right? Not a big problem in a healthy reef tank? When you say organics are the biggest problem in closed systems I have a feeling you are talking about more than phosphates?

icebear · 05-02-2003, 12:20 PM

big, stupid icebear waddles in....

so if metals are a bad thing (at least one of two main potentially bad things) is there any way to get them out of the water? magnets? (kind of joking)

how about sand stirring?

i thought sand stirring was another contraversy within the DSB contraversy (am i spelling contraversy right?)

ok and the sand stirring thing, will that release the metals (bound or unbound) into the water so it can be removed with whatever method metal removing can be acomplished if it exists?

can sand stirring be done regularly on a small scale so that whatever junk (organic or otherwise) is released, some mechanical method of removal can keep up so that a toxic level of release is never reached?

and then the DSB layers thing, i thought certain layers were different parts of this process, but why would it matter to keep these undisturbed layers if its surface area that does the bacterial redistribution of organic waste products....?

Uggh....

no, i think i'm just not getting it.

I want a DSB cause i like the look of it, yes i like the look of a thick layer of sand with LR and colored thingies mounded on the top of it. If my DSB only lasts about 5 years, well...i can't imagine not having to do something drastic with my tanks in 5 years or more (like tearing them down and trading them in for something bigger, smaller or totally different)... I want a DSB on my "Colorful squishy things only" tank (mushrooms, zoos, buttons and leathers) which won't have more than a token fish or two, and i want a DSB in the 75 gallon FOLR which will house a few puffers, my tang, clown and angelfish...one or both will have or share a 30 gallon LR sump in which i plan to try propigating some Tang Heaven mix to supply my yellow monster with fodder.

I don't know if its going to work, but if i don't pull everything apart and its still going after 5 years, i'll let you all know!

Spanky · 05-03-2003, 08:26 AM

>so if metals are a bad thing (at least one of two main potentially bad things) is there any way to get them out of the water? magnets? <

Actually there is, by removing detritus and the bacterial flock associated with it.

>how about sand stirring?<

Stirring the sand, removing the detritus with filter floss or skimming, even vacuuming the sand. Trouble is, with a DSB you can't to that, shallow you can.

>i thought sand stirring was another contraversy within the DSB contraversy (am i spelling contraversy right?)<

Close enough and better than me. LOL Assuming that your particular DSB is working right (they don't always do that) you might not need to. You mileage may vary.

>ok and the sand stirring thing, will that release the metals (bound or unbound) into the water so it can be removed with whatever method metal removing can be acomplished if it exists?<

It will stir up the bacterial flock associated with the detritus and that you can remove.

>can sand stirring be done regularly on a small scale so that whatever junk (organic or otherwise) is released, some mechanical method of removal can keep up so that a toxic level of release is never reached?<

It's called heavy circulation and heavy export of detritus. Skimming, algae filters of some sort (a lot of detritus can be associated with these algae filters), etc

>and then the DSB layers thing, i thought certain layers were different parts of this process, but why would it matter to keep these undisturbed layers if its surface area that does the bacterial redistribution of organic waste products....?<

I think I follow that.

You're going to need a low oxygen zone to process the organic waste.

>I want a DSB cause i like the look of it<

Go for it! They do a great job and are a lot of fun.

>When you say organics are the biggest problem in closed systems I have a feeling you are talking about more than phosphates?<

You bet Tom. I'm talking about not just the organics but all the things associated with organics and all the things that organics make possible. When you look at the whole picture, organics are the biggest problem.

NewReefer · 05-03-2003, 10:02 AM

Quote:

Originally posted by Spanky

It's called heavy circulation and heavy export of detritus. Skimming, algae filters of some sort (a lot of detritus can be associated with these algae filters), etc [/b]

This is one of the best ways we can keep control of our expenditures.

If you think about it these practices are evolving to being part of a total package, the DSB and how to operate it successfully. I hope one day a newbie asks what is a DSB and we point him to this, our guide on how to make & maintain a long-term successful DSB. Even though nothing is forever, the extended benefits out way short term problems and being aware of for coming problems is key. Ten years from now I will probably want to ............think in ten years you will have the same setup?

Tom Hulse · 05-04-2003, 11:50 PM

Quote:

You bet Tom. I'm talking about not just the organics but all the things associated with organics and all the things that organics make possible. When you look at the whole picture, organics are the biggest problem.

Thanks for taking the time to answer my questions Jerel. I think I've been doing a poor job of explaining my question:
What do you mean by "organics"?
If I told you I thought 'toxins' or 'poisons' were our biggest problem you would tell me to be more specific. You'd say 'what toxins?'.
My limited perception is that the major component of organics (and "fish poop") is nitrogenous waste. It's also my humble perception (please do tell me if I'm wrong) that most decent reefers don't have elevated nitrate levels, so I'm led to believe in my own twisted mind

that the major component of organics is not a big problem for us. Therefore I would think you would want to be more specific. What are the toxic components of organics that won't offgas in a nitrogen cycle? You mentioned phosphates was one, what are the others?
Thanks for your patience.
- Tom

Spanky · 05-05-2003, 07:51 AM

Gotcha! what sticks out the most would be any metals. But everyone has been told, led to believe, that all nitrogenous compounds are going to be broken down and off-gassed. In a perfect world, in a perfect DSB/plenum, that would still not be possible because some of these products are just too decomposition resistant and DSB's just don't provide the combination of events to provide this. Spicules, chitin, cellulose, etc all come to mind, even though they are either a protein or carb complex. Bacteria and their products are going to compose most of what's available. I'm pretty sure that most people have a grasp on bacteria, their importance in these types of filters. I'm not sure that it's realized that bacteria compose the bulk of the bio-mass in these systems and how hard it would be for these filters to break down the left over shell walls.

NewReefer · 05-05-2003, 08:17 AM

It is a vicious cycle, it is up to us to replicate it as close as possible, but can we in a closed system? Can we replicate a cycle as complex as our open oceans? Do we even know that complete cycle to replicate it properly? We may be close enough, but if we look into it in dept, we are no way close. So what does one do? Create a small closed system with several systems in place that over compensate for our misgiving's of a complete biological system. Which I guess this discussion is all about, and maybe even improve our small glass cages to replicate this massive system. No matter how you look at it, it is impossible to create a perfect system where this waste matter just disappears, it just doesn't happen, never has, never will. All we can do is manually or mechanically remove what is of hazard to our systems alone with as much natural materials as possible. Now the discussion as of how, is wide open and forever evolving!

Ok I'm sure to get bombed on this one lol!

SAT · 05-05-2003, 09:15 AM

It seems to me that particulate and larger organics in the "difficult to decompose" category can be pretty much ignored. Why treat them any differently than sand if they're inert? Dissolved organics, OTOH, can presumably be removed by changing water or using carbon once they actually leave the sand bed.

Spanky · 05-05-2003, 10:07 AM

Stuart bear with me here, I'm trying to think of a everyday example so this might not be perfect.

Ever notice how in some old sand beds the worm tracks and such will progressively get shallower and shallower? What's happening is that as this (for lack of a better word) end product detritus is building up deeper in the sand bed, you're anoxic zone is also building up higher and deeper. That's also making your ability to process ammonia/nitrite/nitrate less. When people refer to sands beds leaking, this isn't so much a release of nutrients as it is the sand bed is just not able to hide that multitude of sins as well and has lost some of it's processing ability. Over crowding, over feeding, over production in that closed system.

Granted this will not happen the same in every sand bed. Some work and some don't. Some people feed more and some less. Some export more. Some have different corals that are able to process the nutrients directly out of the water. Well you know.

SAT · 05-05-2003, 11:01 AM

Seems like we ought to focus on why the anoxic zones in some sand beds get bigger and others don't. Maybe because some systems don't have the appropriate sandbed fauna? Assuming difficult-to-decompose crap (we need a good name for it

) accumulates deep in the bed, wouldn't that be basically turning the sand bed into a mud bed? If so, maybe after a while we need to repopulate with mud-based organisms.

NewReefer · 05-05-2003, 11:05 AM

THUS THE MUD SYSTEM OR SILT BED!

Spanky · 05-05-2003, 11:06 AM

You guys are so firmly entrenched in this line of thinking. How in this world did that happen?

Nevermind, I just realized.

Stuart, the short answer is you need to hook up an abyss.

NewReefer · 05-05-2003, 11:15 AM

LOL Hey who started it? Maybe I should just dump the whole DSB idea and install a mechanical filter and clean it once a week.

Spanky · 05-05-2003, 11:22 AM

Scott don't laugh, that is a viable option. Keeping in mind that sand and rocks was the oldest way and everything after that was an attempt to improve on that way. Mechanical filters allowed us to keep animals that no one was successful with using sand and rocks.

It all boils down to what animal, what system, what husbandry.

As long you realize that without exception, each way has it's limitations.