righto so, I’ll break it down and compare the three things in question here
1. Aquaculture systems technologies (AST, the presentation) and their attempt to find a viable way to export nitrate from Aquaculture systems to negate the need for water exchange or dangerous forms of nitrogen removal like sulphur based denitrification (can you imagine in a 100,000 litre system holding over 30-40 tonnes of fish what the effect of a sulphur denitrator malfunction would mean??????, one word,........ BOOM), this is not overly mentioned in the presentation, but it based on my talk with AST back when I used to deal with them in my old position at Aquasonic.
2. The use or organic carbon based nutrient reduction in marine aquariums and the bacteria responsible for it (covered in the article posted on the blog)
3. The bacteria related to the reduction of ammonia and nitrite and how these interrelate to the bacteria responsible for the reduction of nitrate in marine aquariums.
Aquaculture systems technologies research into nitrate reduction on a large scale
this is using their filter developed by Dr Ron Malone of Louisiana state university the POLYGEYSER, he created the bubble bead filter and the propeller washed bead filter, the polygeyser uses a pneumatic trigger to backwash and tumble the bed at certain intervals to release biofilms and scrub the biofilm off for removal, as well as solids, this is different to our use of fluid bed filters/reactors to tumble bio pellet, but essentially achieves the same result.
This is independent of a nitrifying filter (like for instance, another polygeyser or other type of bio filter in an Aquaculture system responsible for the reduction of ammonia and nitrite) and is applied for the purpose of nitrate reduction (and solids removal to a certain extent); this can be by two modes.
The first is bacteria (not necessarily nitrate specific) taking up nitrate as part of their cell structure, which then gets stripped out by other filtration, such as a protein skimmer.
The second is nitrate reducing bacteria (such as bacillus denitrificans) which will take nitrate, and reduce it through several conversions, to nitrogen gas (this includes nitrous oxide), and can include the annamox process, as when it is reduced, a by-product can sometimes be ammonia, or ammonium, which can then be reduced in the same anaerobic environment that the denitrifying bacteria (bacillus denitrificans) live.
And that is where it really ends, quite simple, but essentially they are using any means possible to remove nitrate using an organic carbon based substrate/media, and are relying on all of these processes, which are all interconnected, to achieve the job.
Use of organic carbon based nutrient removal in marine aquariums for nitrate and phosphate reduction
This is quite simple and something we have gone over a fair few times, and something I cover in my blog in my signature if you need more info. However, as mentioned, this is independent of nitrification, they put this relationship in the article posted above by advanced aquarist because anaerobic nitrate reduction, annamox (anaerobic ammonia/ammonium reduction, a by-product of nitrate reduction process) and nitrification (the process that starts it all, and is achieved by Autotrophic bacteria that use inorganic carbon such as bicarbonates, not heterotrophic bacteria that use organic carbon forms and the bacteria responsible for nitrate reduction, and its connected by-products in that process such as ammonium/annamox) are BOTH part of the whole picture.
There is no one way to target or specify through dosing or design which one way nitrate is going to be reduced. When you’re talking about nitrification (ammonia into nitrite into nitrate) it is most often achieved by autotrophic bacteria and will be the main vector or transport and reductions for these nitrogenous compounds. But at the end when you need to remove nitrate, it can either by bacterial cell uptake (in an aerobic or anaerobic environment using organic carbon) or it can be reduction of nitrate into nitrogen gas, ignoring the annamox process, this is what happens when nitrate is reduced through several steps into nitrogen gas and is what liberates the carbonates (why alkalinity rises across the bed in the presentation) and is the most common form of nitrate reduction in freshwater aquaria, and one of the way nitrate is reduced in marine aquariums as discussed.
So essentially, you are achieving both, and its best not to think about it otherwise you get what I am sporting at the moment, which is commonly referred to by me as "a headache not unlike one that could bring down a fully grown bull elephant".
Nitrification and how it relates to the above processes
I think I may have covered it anyway but in short, these are two different filtration and biological reduction processes, but they are still related. WHY.... because nitrifying bacteria and denitrifying bacteria, autotrophic and heterotrophic bacteria, will live in the same biofilms. And are all dealing with nitrogenous compounds.
this means that they well and truly could both live in a bio pellet reactor, but the constant scrubbing and availability of organic carbon leads me to believe that in bio pellet reactor the heterotrophic bacteria (responsible for nitrate and phosphate reduction, waste assimilation, annamox) would fast outcompete the nitrifiers and the biofilms of the heterotrophic bacteria would smother them out as heterotrophic bacteria grow much MUCH faster.
So there it is, two or three different modes of nutrient reduction, most of them interrelated either directly (through the nitrogen cycle products ammonia, nitrite and nitrate) or through the types and groups of bacteria used in their reduction (for instance nitrate and phosphate both use heterotrophic bacteria that rely on organic carbon).
Using bacterial supplements is a way to BOOST and accelerate both of these stages, but you have to break it down into the groups of bacteria being used and what products contain which bacteria.
A good bacteria to seed a nitrifying bio filter (start an aquarium or recover one after a bio-filter crash) will tell you it contains strains of nitrosomonas, nitrobacter, nitrococcus, nitrosococcus, nitrospira, nitrosospira, nitrosolobus etc. etc.) and these will be kept in the fridge. WARNING - anyone who tries to sell you a nitrifying bacteria with these strains in it that tell you it can be kept on the shelf and is not keeping it in the fridge is kidding themselves, yes some of these strains can last out of the fridge, but most will die within 3-6 months. They cannot form spores of mucus coating to make themselves inactivate, and who knows how long it’s been since they have been bottled, then sat in transit, then sat at a warehouse before being sent out to the store, then sat on the shelf in the store. Get the nitrifying bacteria that are in the fridge.
You generally only to need to add these once, or if you cycle you tank naturally, not at all, but these bio filter starters do start a tank very quickly and get the right strains in there at the start.
Other bacteria’s such as cycle, stability, stress zyme etc. etc. will contain heterotrophic bacteria; these bacteria can initiate a cycle, but will not directly start a cycle. They are waste assimilators and phosphate and nitrate reducers, some have a good range of different strains, other do not.
The better ones like Zeo-Bac, Microbacter7 &, Bio-Aid will be very efficient waste assimilators and denitrifiers as well as they may also reduce phosphate effectively. These bacteria’s can be stored on the shelf as they are heterotrophic bacteria, but with all bacteria, to slow them down and get the best shelf life and stability, they are best stored in the fridge either whilst waiting to be sold, or when opened.
As I said, these bacteria will break down the waste into ammonia to help the reduction of nitrogenous compounds by the autotrophic nitrifiers, but will not really effectively reduce ammonia and nitrite themselves, at least not effectively.
So what I am getting at is, once a bio filter has been established and you have a stable reduction of ammonia and nitrite and have no readings, weekly/regular addition of these heterotrophic waste assimilating probiotic bacterial mixes (especially when used in conjunction with organic carbon) will allows you to control nutrient better, and FORTIFY if you will, and organic carbon dosing, bacterial driven nutrient control system.
Anyone’s brain exploded yet because I need coffee, nay, beer.
Any questions let me know, info in my blog too, please sign up people, would really like to get people posting questions to my blog posts on there as well.
G
