DSB Diagram -- Seeking Consensus

Hydrogen sulfate is not an issue,; hydrogen sulfide may be.

Setting aside for the moment the question of wether or not potential hydrogen sulfide formation should/not be displayed , a brief clarification on the process may be helpful.

In brief, the bacteria use: carbon,nitrogen and phosphorous for growth and oxygen to metabolize these. . They use all 4 of these elements. A limitation in one or another will reduce denitrifying bacterial activity.For example, a lack of carbon will limit anaerobic bacterial activity and the need to use the oxygen from nitrate,thereby diminishing the denitrification activity.
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Bacteria use nitrate, (NO3) for oxygen in oxygen poor (hypoxic areas ). When nitrate is exhausted if there is still carbon ,phosphorous and nitrogen available, they use the oxygen in sulfate (SO4) producing hydrogen sulfide(H2S) as a by product.













is in the saltwater in the tank at a level of 2800ppm.
 
<a href=showthread.php?s=&postid=15077350#post15077350 target=_blank>Originally posted</a> by therealfatman



IMO High velocity flow is the key to sucess with a DSB whether in tank remote or RDSB. As fast as it can flow while still keeping the sand in place. Unless you like being bound to critters and there dragging nutrients into the sand that should have instead have been removed instead by a skimmer. The constant possibility of a toxic zone and hydrogen sulfide gas due to the work of the critters and slow flow and velocity of flow is reason enough to discourage slow flow in all but refugiums with sand beds. As these are refuges for critters such as pods that need nutrients and particulates and macroalgaes that can utilize organic nutrients better prior to their becoming nitrate.IMO

thanks for joining in and further clarifying

What process (s)do you see in process to get nitrates to the anoxic layer other the work of critters?
 
FWIW, I think that hydrogen sulfide should be included. I almost wonder if the PO4 binding nature of calcium should be included. I know that this starts to get to complicated and it seems the main point of the diagram is the nitrogen components. I am a user of a DSB, but I don't want the diagram to be seen as glazing over the shortcomings of DSB.
 
How does using epsome salts increase the possiblility of producing hydrogen sulfide in the light of what has been discussed on this thread?
 
<a href=showthread.php?s=&postid=15080161#post15080161 target=_blank>Originally posted</a> by capn_hylinur
How does using epsome salts increase the possiblility of producing hydrogen sulfide in the light of what has been discussed on this thread?
Probably not at all. Magnesium is usually present in sea water at a ratio of about 10 to 1 magnesium chloride to magnesium sulfate(epsom salt). By using just magniseum sulfate you do not replicate the ratio of chloride and sulfate and could build up sulfate over time but probably not enough to skew the ratio very much since at normal levels there is already 2700ppm which is more than enough for for hydrogen sulfide frormation.Sulfate is the 3rd most prevalent ion in seawater(other than water) after Chloride at 19,000ppm and sodium at 10,500ppm.
 
<a href=showthread.php?s=&postid=15082445#post15082445 target=_blank>Originally posted</a> by tmz
Probably not at all. Magnesium is usually present in sea water at a ratio of about 10 to 1 magnesium chloride to magnesium sulfate(epsom salt). By using just magniseum sulfate you do not replicate the ratio of chloride and sulfate and could build up sulfate over time but probably not enough to skew the ratio very much since at normal levels there is already 2700ppm which is more than enough for for hydrogen sulfide frormation.Sulfate is the 3rd most prevalent ion in seawater(other than water) after Chloride at 19,000ppm and sodium at 10,500ppm.

thanks ==I was using epsom salts while I was finishing off the last of my IO salt mix. Now I am starting with H2Ocean and am anticipating I won't be using as much 2 part and magnesium with it.
 
Will say more on this later, but wanted to post this new and improved diagram now. Hopefully it improves on things. I did seriously look at including sulfate, but I just don't see a good way to do it. I do fully support including that chemistry information in the accompanying text. So please submit some bullet points to that end.

Thanks for sticking with me guys. :)

DSB_consensus_007.jpg
 
Oh, I am considering changing the bottom "Anaerobic Bacteria" to "'Toxifying' Anaerobic Bacteria".
 
A few suggestions...
1) It's nitrifying / denitrifying... there's no "a" in those words
2) I don't see a reason to include nitrifying / denitrifying / facultative in quotes
3) NH4 is technically ammonium, not ammonia
4) Denitrification results in N2, not just N
 
You know Capn, if you're reading this, I find your announced unsubscription a little egotistical. First, you accuse me of placing "anaerobic bacteria" in the "oxygenated" layer. Which I did not, and yes, your overlooking that made me wonder just how much effort you were actually making in your analysis. That annoyed me and I said so. I then apologized for being irritable, which I was. Now I've refined the diagram, included a couple of your suggests, and yet you find the need to announce that you're leaving the thread without so much as an explanation. Is it really because I didn't include sulfate? Is it really because you just want me to create a chemistry diagram for your own blog? I say again, create your own diagram, Capn. I usually get paid for that.

Now I'm irritable again. :rolleyes:

The only way I see to add sulfate is to place a left pointing arrow on the right side of the anaerobic bacteria in the anoxic/anaerobic layer. But that would literally be coming out of right field and I don't believe would help visual understanding. But I'm willing to hear further arguments to that effect or any other suggestions for how that information could be effectively included in what is becoming an increasingly cluttered and cramped diagram.

Thanks again for everyone's help and sorry for the outburst. But damn it, this things has been work, there is never going to be absolute consensus, and I'm not here to placate egos. I don't think I should be creating this diagram specifically for other members blogs anymore than other members should be creating their blogs specifically for my diagram.

*sigh*...
 
<a href=showthread.php?s=&postid=15091323#post15091323 target=_blank>Originally posted</a> by fsn77
A few suggestions...
1) It's nitrifying / denitrifying... there's no "a" in those words
2) I don't see a reason to include nitrifying / denitrifying / facultative in quotes
3) NH4 is technically ammonium, not ammonia
4) Denitrification results in N2, not just N

Thanks for this, I'll give it some thought.

Capn felt there was a need to elaborate on the bacteria. I've seen those terms used before so thought it might be a good idea to include them so newbies know what people are referring to. But I don't see the point in referring to it as "nitrifying" because it is really the nitrate that is being exchanged between the upper and lower bacteria, thus the first is nitrafying and the second is denitrafying. I am open to removing these terms entirely. Just say why and I'll consider it.

"Facultative" is included because of the confusion that exists between the environmentalist's use of terms compared to the rest. Environmentalist's don't consider the bacteria in the hypoxic/anoxic layer to be truly anaerobic, thus they like to specify that they are simply facultatively anaerobic. It's an important bit of minutia because it explains why environmentalists use the term "anaerobic" for the truly anoxic bottom layer. For them, those are the only truly anaerobic bacteria.

Anyone else want to contribute their thoughts with regards to "ammonium" vs "ammonia" and "N2" vs "N"?

Thanks.
 
Okay, putting it up here for consideration. I really can't do much more than this without graphical suggestions. Please give your thoughts on the bacteria descriptions and the inclusion of sulfate.

Added a bit of artist licence. :)

DSB_consensus_009.jpg
 
I hate to say it, but when I was first starting that would've confused me. It makes sense to me now, but I wouldn't have been able to understand it when I barely understood the tank cycle.

Maybe keep a simpler graph on hand for total noobs and use this for someone who has a better understanding of the basics. Alot of people start with the CC, realise it's a problem, then they start thinking about a sandbed. By that point they usually have at least some grasp of the nitrogen cycle and they could better understand it with the above graph.

I just thought I'd chime in because I'm still fairly new and I am blessed with the scientific smarts of your average ape.

edit:The Gnomes help
 
I don't know if this is intended for the total newbie that doesn't understand the basic tank cycle. It's more for someone that has been exploring the option of a DSB and wants to know more. someone like you and I..that are still newbie's but has a good grasp on the hobbly already. I may be totally off though. Whys?
 
Oh, just realized I put "nitrifying" and "denitrifying" on the wrong bacteria. Need to move each of those down one. But here's the thing. I like the term "reducing" for the bacteria at the bottom, but don't have room for both it, "denitrifying", and the sulfate arrow. So here's the question. Which two of these three are most important?
 
<a href=showthread.php?s=&postid=15092440#post15092440 target=_blank>Originally posted</a> by jasonrp104
I hate to say it, but when I was first starting that would've confused me. It makes sense to me now, but I wouldn't have been able to understand it when I barely understood the tank cycle....

edit:The Gnomes help
Only one gnome helps, the other one is evil. ;)

I appreciate your insights. I have one group of experts pulling me in one direction and another group pulling me in the other. It's frustrating because I'm trying to please both and egos get in the way.

A simpler diagram is not out of the question. I thought I had one once. :lol:

I just need a final clarification on the bacteria names and the inclusion of sulfate. That's it. Without something earth shaking to add, it's done. I would like some bullets from people, especially the experts, on what information should be included in the text portion of this project. A paragraph regarding sulfate reduction seems in order.

Hopefully the accompanying text will help things for any newbies trying to decifer the image.
 
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