Anaerobic Bacteria Cultivation

[ChrisCummins]

Hi,
For a coil de-nitrator I'm working on, I'll need to know what factors affect the growth and health of anaerobic bacteria. Things I'm interested in include:


Flow - I've heard about 3-5 lph works best?
Light - does light levels affect it?
Temp
Location - where they mostly gather. i.e. on bio-balls or on sides of tube etcAnother thing to take into account is the equilibrium between the amount of anearobic bacter either:

Turning the de-nitrator into a nitrate farm
Turning the de-nitrator into a toxic gas farmApreciate any help. :)

Thanks,
Chris

EDIT: the answer to the above question will hopefully also bring the answer to how long should the airline tubing coil be before it goes into the bio-balls chamber. :)

[treeboa]

mine was 31 foot and the flow rate was one drip per second

[ChrisCummins]

Using the Winogradsky column example, I can make a pretty accurate guess at what going to happen in the various stages of the project.

1) The Coil 1-10m - non-photosynthetic aerobic bacteria colonise and produce NH3, NH4, NO2, NO3 (nitrification) etc.
2) The Coil 11-23m - non-photosynthetic aerobic bacteria strip water of O2 and create anaerobic zone, with nitrate reducing (de-nitrification), sulphur reducing, ammonium producing (dissimilatory ammonium production I think).
3) Anaerobic chamber - non-photosynthetic totally anaerobic bacter oxidise sulphates into hydrogen sulphide.
4) H2S rich, O2 stripped water is dumped back into tank.

The last section reveals the flaw in the de-nitrator principle, as it shows that theoretically you're just creating an aquarium toxicifier, not de-nitrator.

The bacteria which caught my eye were the photosynthertic anaerobic green and purple suplhur reducing bacteria, which convert hydrogen sulphide and carbon dioxide into water, hydrogen suplhide and glucose:

6CO2 + 12H2S = C6H12O6 + 6O2 + 12S

So, to encourage the growth of hydrogen sulphide reducing bacteria I would need another, lit chamber?

Thanks,
Chris

[simon garratt]

hate to say it, but why not just couple a remote DSB onto the system and let nature do what its best at. ie saving you the hassle. The risks are lower, the effort and space are considerably less, and you have the added bonus it helps feed your system.

Just seems an awfully complicated, fiddly and less efficient way of dealing with waste imo. The main point being you get no assimilation so your total waste volume has to be broken down to No3 before its removed by this method, rather than only a portion of it, with the remainder locked away in biomass in the case of DSB/SSB's etc.


Regards

Si.

[Johnt]

hate to say it, but why not just couple a remote DSB onto the system and let nature do what its best at. ie saving you the hassle. The risks are lower, the effort and space are considerably less, and you have the added bonus it helps feed your system.

Just seems an awfully complicated, fiddly and less efficient way of dealing with waste imo. The main point being you get no assimilation so your total waste volume has to be broken down to No3 before its removed by this method, rather than only a portion of it, with the remainder locked away in biomass in the case of DSB/SSB's etc.


Regards

Si.

What size would a remote DSB have to be for a 350 Lr tank, I'm thinking of going down this route but was under the impression it would need to be huge to be of any benefit. :confused:

Cheers John.

[simon garratt]

completely the oposite John.

in a DSB of just 12x12x4" deep using aragamax or any other fine silt like substrate, theres around 5000sqft of surface area for bacterial growth. Make that 24 x 12 (a more sensible minimum size for DSB imo, and youve got around 10,000 sqare feet. Thats a hell of alot of filtration capacity for the space used.

If its well colonised with critters and is made of the right materials youd be amazed at just how much waste a good established DSB can handle in comparison to our clumbsy technological alternatives.

regards

Si.:)

[Johnt]

completely the oposite John.

in a DSB of just 12x12x4" deep using aragamax or any other fine silt like substrate, theres around 5000sqft of surface area for bacterial growth. Make that 24 x 12 (a more sensible minimum size for DSB imo, and youve got around 10,000 sqare feet. Thats a hell of alot of filtration capacity for the space used.

If its well colonised with critters and is made of the right materials youd be amazed at just how much waste a good established DSB can handle in comparison to our clumbsy technological alternatives.

regards

Si.:)
Thanks Si, I'll give it a go, would it make much difference having it deeper than 4" or is 4" the optimum depth.

John.

Ed : Sorry to hijack your thread Chris.

[ChrisCummins]

Ed : Sorry to hijack your thread Chris.

lol no probs, it's interesting. :)

The reason why I'm experimenting with the de-nitrator is that I already have all the parts, so it'd seem stupid not to make it having spent the money. :D

Thanks,
Chris

[simon garratt]

Fair comment Chris. experimentation is the way to invention and all that.:)


Theres a fair bit of debate over the depth issue John. suffice to say im a fan of the 4-6" theory. Without going into too much detail, i cant see with superfine substrates any advantage in going deeper with the limitations we have regarding the type of diversity required for deeper beds.

regards

Si.

[ChrisCummins]

I've had a brainwave:

what about a cryptic system? They need low flow and dark if I remember correct? Anyone got any info/experience with them?

Thanks,
Chris

[simon garratt]

Im playing with this on the new system Chris, Cryptic zones and combined SSB's

should prove interesting:D


regards

Si.

[ChrisCummins]

Cool cool, any good online reading I could have a look at just to brush up on them and grap the basics?

[simon garratt]

Steve Tyree has a book out i recal on cryptic zones and gave a good talk at the D&D seminar last year. anything by him on the subject is pretty much at the cutting edge to be honest on these low flow low light regions.

Adding an SSB in the same area is just an idea im toying with that will take a bit of thinking and jigging with before i actually go for it, seeing as theoreticaly it 'shouldnt' work. or at least, not very well.

regards

Si.

[ickypimp]

Using the Winogradsky column example, I can make a pretty accurate guess at what going to happen in the various stages of the project.

1) The Coil 1-10m - non-photosynthetic aerobic bacteria colonise and produce NH3, NH4, NO2, NO3 (nitrification) etc.
2) The Coil 11-23m - non-photosynthetic aerobic bacteria strip water of O2 and create anaerobic zone, with nitrate reducing (de-nitrification), sulphur reducing, ammonium producing (dissimilatory ammonium production I think).
3) Anaerobic chamber - non-photosynthetic totally anaerobic bacter oxidise sulphates into hydrogen sulphide.
4) H2S rich, O2 stripped water is dumped back into tank.

The last section reveals the flaw in the de-nitrator principle, as it shows that theoretically you're just creating an aquarium toxicifier, not de-nitrator.

The bacteria which caught my eye were the photosynthertic anaerobic green and purple suplhur reducing bacteria, which convert hydrogen sulphide and carbon dioxide into water, hydrogen suplhide and glucose:

6CO2 + 12H2S = C6H12O6 + 6O2 + 12S

So, to encourage the growth of hydrogen sulphide reducing bacteria I would need another, lit chamber?

Thanks,
Chris
chris to be honest the biggest issue you will face is halotolerance, the best bacterium by far for the job is thiobacillus denitrificans (i have a culture at work) this would mean moving from the pvc tube model to a sulphur reactor but it will work, you will also beed a chanber with some calcium carbonate for the resulting water to flow through as you basically end up with a weak sulphuric acid solution, the carbonate brings the ph back to a reasonable level and will release calcium ions

the hydrogen sulphide can be addressed with rowa... in industrial environments iron oxides are used to chelate hydrogen sulphide

[manda]

flow - depends on lenght of tube faster flow means you need more length before it becomes oxygen limiting

light - most nitrifiers and denitrifiers prefer the dark

temp not worth trying to overheat but higher temps 30ish increase rate quite a bit, mabye put by heater for system, higher temps favour nitrosomonas slightly, sharon process utilises this to wash out nitrobacter which if you want classic denitrifiers may not be a cunning plan).

location, mostly gather nowhere, mostly grow where theres little oxygen, thick biofilms and flocs of nitrifiers often have underlying denitrifier populations underneath where they have cut of the oxygen. crevases of lie rock, or just wait for them to seed from the air in your house!

biggest problem is nothing is static, when you setup there will be little bacteria on the walls of the tube and it probably wont decrease the oxygen for a while, as the biofilm grows more bacteria = more oxygen removal, after a few months you may wel have denitrification in the tube itself both uner the nitrifier populations and towards the end of the tube, till you reach steady state when the natural sloughing of the film will be constant flow wil have reduced by then due to the increased roughness of the pipe wall and smaller available crossectional area for flow. even then lenght required will be soo variable dependant on what bacterial pops you have, parameters of the water entering etc etc, could spend weeks calculating and still not have good answer.

IMO best bactera for the job are from anammox group but only cos i luff them and spent far too long studying them.
- dont need to risk the hydrogen sulphide production cos they live at low oxygen concs, need less additions (esp of alkali and carbon) to system as nitrite-nitrate then nitrate - nitrogen gas steps are missed, sainvg oxygen too. problem is tho that like wih anything you innoculate with one and unless your running a clean system others (nitrobacter et al) will populate and nitrate is formed, then your stuck with the denitrification or nutrient export routes.
- theres theoretically a risk of the anammox dieing out and leaving you with nitrite peaks, tho i found them a hell of a lot more robust than many denitrifiers in the freshwater environment.

think as with everythign its best to have as diverse a range of bacterial strains as you can, when did spike and prolonged testing with contaminants mixded wild cultures recovered fastest and best. pure systems are weak if you get sommet wrong with the water having as rich a biodiversity as you can means that hopefully somet will survive if you by mistake spill tolluene in your tank, lol not so much of a problem for fishkeepers but for municiple waste water treaqtment works its a real worry.

for what its worth, i have v little piping to a bioballs container, started off with loads, kept smelling the end for denitrifiers, (they have weird distinctive odor, cant explain it if you can get to a sewage plant and smell the denitrification units you'll never forget it kinda tinny) and cutitng off the piping till i couldnt smell it then reattaching, ended up reaching limit of the metre between units so now up the flowrate as the biofilms get thicker inside as well it just keeps goign up and up, started of at a few drops a minute, now have a relatively fast flow i always try and make sure theirs a small amount of nitrate in the outlet (which isnt all that easy when the test kits are so innacurate, but go for a hint of colour as apposed to totally clear, in prectice now have macros have prectically gicven up ion this but at the begineing was how i did it). as long as the denitrifiers have sufficient nitrate as an electron acceptor they will not tend to use sulphates. just as if there is oxygen present the bacteria will use it as an electron acceptor instead, the payback is bette ie metabolism is much more efficient with nitrate than having to reduce suphur but if there isnt nitrate they gotta make a living somehow. easiest way to understand it is like with yeast, in bread making yeast uses oxygen with carbohydrates to produce carbondioxide (hence bread rises) in absence of oxygen it cannot fully metabolise it so produces alcohol (beer et al). not exactly the same principle as co2 and C2h5OH are the waste products not the electron accepters and the feedstuf is the same, but its as close as i can think of at the mo.

however being away form home for weeks sometimes i get back and i hadnt turned it up enough last time, so, whenever i smell sulphur dioxide in the outlet of the bioball container, i turn up the flow, discard the first 3 volumes that come out to not poison system more than it has in the time its been going too far, then put outlet back into sump and leave it running again.



argh minni jbberish essay, sorry!
plz excuse the dyslexic ramblings, hope it helps
manda

[ChrisCummins]

Thanks alot for the input! :)

I'm just gonna have a lie down now then read through everything again. ;)

Thanks,
Chris