Multiple Source Carbon Dosing
- Thread starter MikeYQM
- Start date
I believe that in that post he is expressing an opinion that has no supporting evidence that I have ever seen, and the last part doesn't even make sense to me.
That seems like a reasonable dose.
What do you want it to accomplish that it hasn't yet done?
Mike_Noren
New member
Well, there is a possible theoretical reason why one might want to dose both alcohol and acetic acid: they appear to be metabolized by different denitrators.
That paper also gives a possible reason why dosing sugar may cause discomfort with sensitive organisms (ammonia build-up).
That paper also gives a possible reason why dosing sugar may cause discomfort with sensitive organisms (ammonia build-up).
Why is it an advantage to employ more than one species of denitrator?
MikeYQM
New member
Initially simply to lower the pH of the lime top off water. But now I'm also going to see if there is an advantage biologically.
MikeYQM
New member
I suppose that is what we are trying to determine. Perhaps one or several species are more suited to out compete algae or undesired bacteria.
I am quite certain that some species are more prone to outcompete other organisms than are other species, and that one or more is the one which will win out long term. But there is no reason to think you'll get a better competitor with 3 carbon sources than 1.
Well, it should reduce the pH in the tank, but the limewater will still have a very high pH.
Oh, OK, that's certainly fine. I misunderstood. I thought you were looking for an effect of some sort and hadn't seen it. 
Mike_Noren
New member
All the usual hypothetical advantages of diversity: Two pathways are generally more resilient to disturbances than one, two sets of bacteria may be more efficient than one, and of course the two sets of bacteria may use different areas of the tank.
It's all speculation of course, because I don't know exactly how the carbon is utilized or by whom, or exactly where the nitrogen and phosphorus goes. It's been 13? years since I first dosed dextrose in my tank, and to me the process is still a black box.
MikeYQM
New member
My original question was regarding a different effect. However that's not the main purpose for vinegar addition. I am curious to see if any differences will be noted with the additional carbon source.
I have the luxury of an extremely stable system in all parameters so any difference should be detectable.
I have the luxury of an extremely stable system in all parameters so any difference should be detectable.
Well, I don't buy the fact that those are even hypothetical advantages. I could just as easily state every one in reverse (and I do at the bottom).
Sure, two different sets of bacteria growing on two different carbon sources might be less susceptible to certain rare destructive events, such as something pathogenic killing off the bacteria.
But what exactly would the consequence be if that happened? I contend in any case, another species will just move into place and take over metabolizing the available organic, whether that was the only organic around, or one of 3 being dosed. I fail to see any big problem with that. It's not like the case of a farmer crying over lost corn crops because of locusts.
two sets of bacteria may be more efficient than one
How could that be? If it were true then the concerns about monocultures would be invalid as even with a single carbon source, there may be many species growing because, for this stated reason, more than one species is more efficient than one.
and of course the two sets of bacteria may use different areas of the tank
Yes, that's possibly true. If you get a species growing in a visible part of the tank, like cyano in the main tank, you might want to switch to a different carbon source and hope you get a species growing where you want it, out of site somewhere. I'd guess that more different species tyou drive with different orgnaic carbon sources, the more likely you are to ge tone thriving some place you do not want it.
So here's the restatement:
All the usual hypothetical disadvantages of diversity in organic carbon dosing are reduced by dosing a single carbon source:
1. The single most useful organic can be chosen which is most effective in driving bacteria where you want them and not where you do not.
2. The single most useful organic can be chosen which is most efficient in driving bacteria as opposed to cyanobacteria and other undesirable bacteria.
3. The single most useful organic can be chosen which is most efficient in driving bacteria to reduce nutrients the most.
4. One strain is less likely to have problems than two, because there are half as many bacterial species likely to become food for something that eats them all.
Mike_Noren
New member
First of all I'd just like to say that I don't personally dose more than one carbon source, and personally don't think it matters to the health of your tank if you dose one source or more. So with the understanding that I'm the devil's advocate:
One doesn't have to wipe out one pathway to have benefit from having more than one. Also e.g. changing temperature or pH or dissolved oxygen or availability of nitrate might temporarily be disadvantageous to one group but not the other, allowing the system as a whole to remain stable.
Oh I'm sure there's much more than two species at work in any reef tank, and this is why I don't think it really matters how many types of carbon is dosed, there will be sufficient diversity to maintain stability anyway.
That said, if it was somehow possible to create just a monoculture of one type of denitrifying bacterium, I'd expect that system to be extremely fragile, regardless of how efficient that bacterium was: monocultures are inherently unstable and require constant support to avoid collapse. Cf a corn field or a salmon farm.
Well, I was thinking more along the lines that if they have different environment preferences (e.g. if one lives on sand grains and the other inside sand grains) they effectively increase the area available for denitrification, but aesthetic concerns are of course also a factor, yes.
Like I said I don't really have any problem with dosing just one type of carbon - it is what I do myself.
I prefer vinegar to vodka in my system. Vodka seemed more prone to cause cyano. That may not apply to all systems by any means, but a few folks have experienced that relationship. There is also some supporting scientific literature data for that difference.
I don't prefer pellets for a variety of reasons (control, timing, cyano, etc), but I've not actually tried them in my tank.
OK, I guess I can't claim there are no hypothetical advantages as you've hypothesized several.
With respect to stability, that may be true, but unlike a salmon farm, if one species collapses, another will just swoop in and take its place. For all I know, that has happened in my tank many times already.
Tanks are idosynchratic as are their keepers. Organic carbon sources are varied beyond what we dose . Autorophic organisms contibute it, foods, waste ,impurites in supplements and salt mixes ,are examples. For the most part it's complicated black box full of tiny pieces moving and changing at highspeed.. Coral holibonts and symbionts and the probable effects of the organic mix on them complicate it further. Trace element metabolism is another twist. Surface area, hypoxic zone availability ,lighting add to the myriad of variables.
Dosing organic carbon in one form or another ( polymers, monomers,ethanol. acetic acid) plays against a backdrop of complex organics indigenous to a particular reeftank and their effect on reef chemsitry and life in the tank.So, picking one or the other or several carbon sources is matter for experimentation and may yeild variable results in different tanks .
I think,however that the type of carbon source dosed influences the organization of the organics in different ways and does matter.
. A carbohydrate including biodegraable plastics or monmers like glucose/dextrose will encourage a more complex chain of bacterial activity as it degrades than acetic acid or ethanol For me that complexity coupled with negative experiences with sugar by me and others ,ie glucose and bio plastics seems to have greater potential to upset existing balances in a reef tank than sources closer to acetate would.
Dosing organic carbon in one form or another ( polymers, monomers,ethanol. acetic acid) plays against a backdrop of complex organics indigenous to a particular reeftank and their effect on reef chemsitry and life in the tank.So, picking one or the other or several carbon sources is matter for experimentation and may yeild variable results in different tanks .
I think,however that the type of carbon source dosed influences the organization of the organics in different ways and does matter.
. A carbohydrate including biodegraable plastics or monmers like glucose/dextrose will encourage a more complex chain of bacterial activity as it degrades than acetic acid or ethanol For me that complexity coupled with negative experiences with sugar by me and others ,ie glucose and bio plastics seems to have greater potential to upset existing balances in a reef tank than sources closer to acetate would.
Similar threads
