The AEQUILIBRIUM project in brief

When we began developing the Aequilibrium protocol (almost 10 years ago), we had a very specific mission in mind: to develop a complete, effective, innovative microbial consortium based on solid scientific studies.

The goal of our research was to build the perfect bacterial “micro-library” for a reef aquarium, then develop a consortium that could handle all the nutrients typically found in reef aquariums, making it easier for hobbyists to manage and solve their problems.

This meant selecting beneficial marine bacteria, having them coexist in stable consortia, ensuring that they remained viable once conditioned, and, most importantly, became rapidly activated in the tank.


In our field, many outdated ideas about bacteria persist, often based on partial, inconsistent, or even biased information.

To explain and demonstrate the capabilities of our bacterial blends, and highlight the extensive research and development that supports them, we decided to re-submit each formulation to metagenomic analysis, in collaboration with the laboratories of the University of Ancona.

The samples were performed by individually activating the contents of the capsules in a standard amount of synthetic seawater (ultrafiltered and sterilized by autoclaving at 121 °C).
They were then cultured in a photobioreactor conditioned in line with the chemical-physical parameters typical of our systems (t°, pH, redOX, NPK, oligo...).
This allowed us to more precisely identify who is inside, in what quantities and with what metabolic potential.

The goal is to share with the community a more "scientific and careful" look at our bacterial activators.

We are happy to offer you a broader view of the "hidden" metabolic processes: to date, no other similar reef-keeping product is supported by such detailed analyses, sequencing data, and metabolic process specifications.


BEA AEQUILIBRIUM is a truly extremely innovative family of products, and we are truly proud to be among the first in the world to present a multi-blend portfolio in which each formulation is based on the adaptation to our sector of the latest innovations in environmental and industrial microbiology .

With AEQUILIBRIUM AEZ-PRO , we wanted to develop “engineered” consortia that mimic – in composition and functions – the microbial complexity of a marine ecosystem .
Designed for precise ecological functions , with highly unique key species , “backup team” systems , and a high metabolic spectrum. Our NGS analyses confirm >40 taxa per product, concentrations of 5x106 CFU per capsule, capable of eliminating a huge range of nutrients and pollutants, and with a viability greater than 95% at 12 months;

The premises are excellent, but what exactly are we talking about?

Which taxa? Which metabolic pathways? Which nutrients?

In this short focus, we will try to give you a glimpse of our work, the rationale behind our choices, and above all, the functional capabilities of our bacterial blends.

High definition portrait of the four blends

Below I have tried to convey to you, in an extremely simplified manner, some of the main bacterial species on which our formulations are based, ordering them according to their percentage abundance within the various mixtures.
For each genus, one of the metabolic pathways that led us to select it for that particular function is mentioned.

Each blend was developed with a systems microbial engineering approach : a “ Core Team ” of strains selected for key metabolic functions , supported by a complementary “ Backup Team ” on the sidelines, ready to ensure stability and functional resilience in case of problems.

AEQUILIBRIUM A – Autotrophs, initiation and stability

The aim is to “ start the bacterial cycle and keep it stable” : in blend A, bacteria coexist that share the entire nitrogen cycle, rapidly colonize rocks and biomedia, and slow down the oscillations of ammonia, nitrites and nitrates.

The “go ahead” is given by Bacillus with its ultra-resistant spores: thanks to the perfect balance of nutrients present in the organo-mineral matrix, the spores germinate in a few hours and colonize the surface of sand, rocks and substrates.

These also release a first flush of proteases and amylases that pre-digest the organic microparticles, preventing them from generating NH₃.
Pseudoalteromonas works right next to it , secreting antibiofilm and anti- Vibrio metabolites: these molecules exterminate the first opportunistic pathogens and leave the surfaces clean for the actual nitrifiers.
The bulk of the “chemical cleaning” falls to Alteromonas , a marine copiotroph armed with CAZymes and siderophores : it breaks down protein residues and polysaccharides into assimilable fragments and steals iron from start-up algae, slowing their explosion.

The autotrophic backup team operates in the background.

Oceanospirillum oxidizes volatile organic acids even within biomedia and substrates with reduced O2, depleting fuel for ammonium spikes.
Rhodobacteraceae attack the first stage of nitrification and produce B₁₂ which helps the first newly introduced benthic organisms.

If nitrite takes a hit, the JGI_0000069-P22 clade comes into play: it has genes for nirK / norB and oxidases that convert NO₂⁻ to NO₃⁻ and dampen oxidative peaks.

Further back, but still valuable, the SAR324/NB1-j group fixes CO₂ and closes sulfo-autotrophic rings in the anoxic zones of the filter, while a veil of Synechocystis photosynthesizes on the surface of the sand and rocks, releasing O₂ and buffering the pH.

The result in the tank: ammonia remains below the threshold, nitrite peaks more briefly, and nitrate stabilizes without aggressive carbon dosing; the rocks are populated with beneficial biofilms, the start-up algae struggle to establish themselves, and the nitrogen cycle runs smoothly after just the first few weeks.

In short:

CORE TEAM – nitrification start

• Bacillus – spores + protease/amylase, immediate biofilter start
• Pseudoalteromonas – antibiofilm, slows down Vibrio pathogens and opportunists
• Alteromonas – CAZymes, siderophores, DOC “vacuum cleaners”

BACKUP TEAM – nitrogen safety net

• Oceanospirillum – β-oxidizes organic acids even at low O₂
• Rhodobacteraceae – initial nitrification step + vit. B₁₂
• JGI_0000069-P22 – nitrite oxidase + ROS detox
• SAR324/NB1-j – sulfur-oxidizing/CO₂-fixing autotroph
• Synechocystis – photo-O₂, pH buffer

AEQUILIBRIUM E – Heterotrophs, organic and nutritious

The goal is to “ dispose of whatever nutrients are in the tank ”: inside it coexist bacteria capable of attacking practically every category of organic compound that a home reef can accumulate — from proteins in uneaten food to lipids in plankton, from the slimy polysaccharides of coral mucus to the free micro-hydrocarbons in seawater.

The demolition work begins with Alteromonas .
This copiotroph carries with it batteries of CAZymes (glycose-hydrolase enzymes, pectinases, alginases) and a suite of extracellular proteases that “fray” complex debris into shorter chains; in parallel, it secretes siderophores that steal iron from opportunistic algae, making the water less favorable for unwanted blooms.

Oleibacter, on the other hand, intervenes on lipids: a true specialist in the β-oxidation of fatty acids and micro-hydrocarbons.
Thanks to enzymes such as alkane-monooxygenase and thermostable lipases, it breaks down the oily “film” that often forms in sumps and skimmers when feeding is abundant.

The protein and anti-biofilm scene is shared with Pseudoalteromonas , whose brominated metabolites not only break down viscous matrices but also keep pathogens such as Vibrio under pressure. These molecules also lower surface tension, facilitating the flocculation of organic colloids that the skimmer can then export.

On the “jack of all trades” front, the emerging clade JGI_0000069-P22 stands out: genomic analyses reveal dozens of pathways for the detoxification of ROS, the oxidation of sulfur compounds and the degradation of amines and DMSP released by corals and macroalgae.
In practice it acts as a chemical shock absorber when the organic load increases or the system enters oxidative stress.

Then, to support the food chain, come:

• Oceanospirillum which completes the β-oxidation of volatile organic acids even at low oxygen
• Bacillus which, once the spores have germinated, releases a cocktail of proteases and amylases and flocculates the organic particles: a natural turbo for the skimmer.
• “Minor” taxa of Flavobacteriaceae , Marinobacter , Alcanivorax and co., ready to refine aromas, aldehydes and refractory polysaccharide fragments that elude the “big players”.

The result of this heterotrophic task force is visible in the tank: the water remains clear with less “yellow” foam, the PO₄³⁻ decreases indirectly because the phosphorus is incorporated into the bacterial biomass (then eliminated by the skimmer) and the odors from stagnant organic matter disappear.

AEQUILIBRIUM E is not a simple probiotic but a true “liquid digester” that transforms — or exports — any organic waste before it becomes fuel for algae and cyanobacteria.

In short:

CORE TEAM – degrades and metabolizes any organic waste

• JGI_0000069-P22– numerous N & S metabolic pathways, ROS detox
• Alteromonas – polysaccharidase/protease enzymes, cleaves DOC complex
• Pseudoalteromonas – antibiofilm, colloid coagulant, foaming enhancer
• Oleibacter – β-oxidizes lipids and micro-hydrocarbons, reducing oily films
• Bacillus – extracellular enzymes, organic absorption, assimilative metabolism

BACKUP TEAM – Nutrient Refinement

• Oceanospirillum – blocks volatile organic acids, stabilizes ORP
• Flavobacteriaceae – coral mucilage hydrolases and biofilms
• Marinobacter + Alcanivorax – oxidize aromatics/oils/hydrocarbons

AEQUILIBRIUM Z – Enzymes, biofilm breaker

The ultimate goal of the Z blend is to "dissolve mucilage and gelatinous agglomerates . " This blend comes into play when pumps, equipment, pipes, and rocks become covered in the "slime" that suffocates corals after thermal stress, relocation, or long periods of neglect.

The work begins with Pseudoalteromonas .
We have talked about it several times, but here its presence is record-breaking: the polysaccharidases it produces “cut” alginates and laminarins, while the brominated metabolites exterminate Vibrio and other unwanted inhabitants before they can rebuild the biofilm.
Bacillus comes into action immediately afterwards: as already seen in blends A and E, its spores germinate in a few hours; in AEQUILIBRIUM Z we are mainly interested in the lipases, proteases and DNases which liquefy the gelatinous matrix, transforming it into flakes that are easy to export with the skimmer.

When the “jelly” begins to flake, the backup team comes into play.
The JGI 0000069-P22 clade—already described in detail in E and P—neutralizes oxygen radicals released by slime lysis, preventing oxidative stress in invertebrates. Cobetia captures the phosphates released during the process: it immediately chelates the nutrient and secretes a thin layer of EPS (slippery exopolysaccharides) that prevents mucilage from adhering. A “biological degreaser” is then needed: this is the role of Pseudomonas , whose biosurfactants lower surface tension by detaching the last gelatinous flakes. Meanwhile, Ruegeria (already a key player in the PRO blend) sends quorum-quenching signals that silence filamentous and thick biofilm-forming bacteria, all while enriching the water with vitamin B₁₂ to reinvigorate stressed corals. Oceanospirillum closes the scene: as we have already explained in A and E, it completes the β-oxidation of the lipids released during the lysis of the agglomerates, maintains a high ORP and leaves the water visually more crystalline.

What do you see in the tank? Once an initial mechanical removal has been applied, the residual mucilage is digested within 48–72 hours, the redox potential increases, and the phosphates remain trapped in the bacterial biomass that the skimmer eliminates. After a few weeks, you can easily notice that the surfaces remain clean and unattractive to cyanobacteria and filamentous algae: this is a sign that Z has not only " degreased" the tank, but has also made it safe from further colonization.

In short:

CORE TEAM – dissolves bacterial agglomerates and combats gelatinous mucilages

• Pseudoalteromonas – polysaccharidase enzymes + antibiofilm bromophenols
• Bacillus – broad-spectrum lipase/protease

BACKUP TEAM – finishing and regrowth prevention

• JGI_0000069-P22 – anti-ROS oxidase/peroxidase
• Cobetia – PO₄ claw, deposits protective EPS
• Pseudomonas – biosurfactants that detach mucilage from substrates
• Ruegeria – quorum quenching + vit. B₁₂, defense against pathogens and opportunists
• Oceanospirillum – eliminates post-lysis lipids, degrades agglomerated residues

AEQUILIBRIUM P RO – Balancing and boosting the microbiome

The watchword is “maintain balance and react to the unexpected” : the P RO blend brings together bacteria that stabilize parameters, repair gaps in the microbiome after moments of system stress or biocide treatments, and provide valuable micronutrients to corals.

The main protagonists here are essentially three, as the first of the “big players” we find again our JGI 0000069-P22 .
As we have already explained for blend E, this emerging clade possesses genomic pathways that detoxify oxygen radicals and oxidize sulfur compounds.

Working alongside it is Ruegeria , a coral symbiont capable of producing vitamin B₁₂, antioxidants and quorum-quenching signals: these molecular messages nip in the bud the bloom of pathogens such as Vibrio .
Additionally, Ruegeria metabolizes DMSP, which animals release under stress, helping maintain balance in the system.

The triangle closes with Halomonas , an osmotolerant and very robust bacterium.
Its denitrase enzymes reduce nitrates without the need for aggressive carbon dosages, making daily management decidedly “low-maintenance”.

In critical moments, the Backup team's support team intervenes.
Oceanospirillum — already described in blends A and E — completes the β-oxidation of volatile organic acids and helps maintain high ORP when the PRO dosage releases inorganic nutrients.

Pseudoalteromonas , which we discussed in detail in blends A/E/Z, secretes brominated metabolites that prevent biofilms and cyanobacteria from reoccupying newly cleaned surfaces.

Then there is a micro-court of specialists: Actinomarinales and Ilumatobacter that refine the most refractory algal polysaccharides; Bdellovibrio /OM 27 patrol the tank, preying on residual Gram-negative bacteria; finally, Desulfobacteraceae reduce sulfates and detoxify any H₂S that forms in deep sandy beds and any anoxic areas.

But what do you see in the tub ?

Thanks to this microbial direction:

• nutrients remain stable and low , with no spikes in nitrates or phosphates during periods of loading;
• the microbiome recovers quickly after antibiotics, blackouts, or other systemic stresses;
• corals receive a constant flow of vitamins and antioxidants, counteracting the presence of any pathogens and opportunists;
• Biofilms and cyanobacteria struggle to re-emerge , because the surfaces remain “surveilled” by Pseudoalteromonas and microbial predators.

In other words, when A EQUILIBRIUM A has already turned on and stabilized the “biofilter”, AEQUILIBRIUM E has cleaned the water column and AEQUILIBRIUM Z has cleaned rocks and surfaces, AEQUILIBRIUM P RO maintains the “shape” of the bacterial team day by day and prevents a single sudden change from throwing everything back into play.

In short:

CORE TEAM – long-term balance

• JGI_0000069-P22 – chemical “air-bag”, numerous metabolic pathways, mature marine biofilms
• Ruegeria – vitamin B₁₂ + quorum quenching, defense against pathogens
• Halomonas – salt denitrase tolerant

BACKUP TEAM – surveillance and balancing

• Oceanospirillum – β-oxidation of residues even with low O2, stabilizes ORP
• Pseudoalteromonas – antibiofilm, keeps surfaces clean
• Actinomarinales + Ilumatobacter – degrade fibers and algal residues
• Bdellovibrio /OM27 – Gram-negative predators, pathogen control
• Desulfobacteraceae – sulfate/H₂S reduction, detoxification of anoxic substrates

The “ minor ” taxa , a glimpse of the secret recipe

As we have seen so far, the sequencing tables show that, in addition to the Core and Backup Team , each blend contains a “silent vanguard” of species that, individually, do not exceed 1–2% of the total but, combined, reach 15 to 22% of the biomass and contribute about a third of the functional genes unique to the entire consortium.
In samples A, E, P and Z these microorganisms push the Shannon index from 2.5 ± 0.1 (without them) to 3.4 ± 0.1, bringing the complexity of the product closer to that of a mature reef.

Minor Taxa in AEQUILIBRIUM A – A Belt of “Finishers”

In sample A, metagenomic analyses reveal Actinomarinales , Aminicenantales , Haliangium , Halioglobus , and the predatory Peredibacter group.
Actinomarinales and Aminicenantales complete the breakdown of insoluble polysaccharides, while Haliangium and Halioglobus form very thin EPS biofilms that keep cyanobacteria away.
Peredibacter, on the other hand, keeps senescent Gram-negative cells under control.
The combination of these functions explains why, at the same organic load, blend A shows shorter ammonia oxidation times than a consortium without this “finisher belt”.

Minor taxa in AEQUILIBRIUM E – Oxidation- reduction microlaboratories

In blend E , Cobetia , Saccharospirillum , Actinomarinales and Peredibacter appear, but above all small quantities of Photobacterium rich in luciferase and flavin-independent enzymes.
Cobetia chelates free phosphates during peaks of organic lysis; Saccharospirillum oxidizes volatile fatty acids under low O₂ conditions; Photobacterium , thanks to its light-dependent respiratory chain, drains ROS when the aquarium is irradiated at full spectrum.
The result is a system that better withstands post-feeding redox swings and which, according to laboratory tests, recovers the initial ORP on average 20% faster than mixtures that do not include these metabolic niches.

Minor Taxa in AEQUILIBRIUM Z – The Last Slime Demolishers

In the Z mixture, the antimucosal action of Pseudoalteromonas and Bacillus is amplified by strategic minorities: Cobetia , which sequesters the phosphates released by the lysis of mucilage; Pseudomonas , which produces natural rhamnolipids, lowering surface tension; Halioglobus , Cyclobacteriaceae , and traces of Desulfobacteraceae , which absorb sulfates and residual aromatic fragments.
After treatment, the biofilm no longer finds ready nutrients and, measured after 72 hours, the TOC is 25% lower than controls without this “finishing crew”.

Minor taxa in AEQUILIBRIUM P RO – Balance between predation and vitamin synthesis

The PRO blend hosts a small but significant population of Anaerobacillus , Bdellovibrio / OM27 , Ilumatobacter and Gracilibacteria .
Anaerobacillus reduces nitrates without accumulating N₂O, acting as a “relief valve” when organic carbon supply drops.
Bdellovibrio is the predator that mows down sporadic accumulations of Vibrio in less than 24 hours, while Ilumatobacter and Gracilibacteria release biotin, tocopherols, and rare cofactors that help corals heal after minor mechanical stresses.
The combined presence of these taxa explains the speed with which the PRO blend recomposes the microbiome after antibiotic therapies: the “deep” functional diversity is never completely lost and the dominant strains can rejoin an already established ecological network.

Overall effect on biodiversity

The “minor” species not only increase the total number of taxa and consequently the Shannon index of microbial biodiversity, but above all bring about 140 additional KEGG pathways centered on vitamin synthesis, ROS detoxification, PAH β-oxidation and reduction of sulfur and nitrogen oxides.

In our pilot plant tests this translates into:

• faster pH and ORP stability after load swings;
• less need for carbondosing because the minor denitrases work “in the shadows”;
• surface of rocks and sand that remains clean, with a thin but functional biofilm, unattractive to cyanobacteria and filamentous algae.

In conclusion

If the main strains are the engine and the backups are the bodywork, the minor taxa are the firmware that optimizes consumption, guarantees redundancy and projects the consortium into the long term.

The sequences obtained from the latest analyses and the reports drawn up not only validate the intuition we had seven years ago, but also allow us to deliver to the reefkeeping community one of the most complete metagenomic profiles available today, where even the apparently negligible content of a Rugeria or an Oceanospirillum makes the difference between a good “ classic ” all-in-one product and the technical and functional depth of our AEQUILIBRIUM PROTOCOL .

Okay, we did it. I tried to make it as understandable as possible, and I hope I did it this time.
I apologize to the advanced technicians but to make it humanly readable I had to do
cuts and simplifications.

I'm once again providing you with some updated bibliography, which is as useful as basil on tomato sauce, and we'll get ready for the next one.

Bonus spoiler: We've been working on bioboost for a year now... If this seemed interesting to you, wait until you see how its variations develop—I assure you, it's something to dream about.

Happy reefing everyone!

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• Omar AA et al. (2024) “Effects of the Putative Probiotics Bacillus licheniformis , B. pumilus and B. subtilis on White-Leg Shrimp, Immune Response, Gut Histology, Water Quality, and Growth Performance.” Open Veterinary Journal 14 (1): 144-153. https://doi.org/10.5455/OVJ.2024.v14.i1.13
• Chen Q. et al. (2024) “Bottom-Up and Top-Down Controls on Alteromonas macleodii Lead to Different Dissolved Organic Matter Compositions.” ISME Communications 4 (1): ycae010. https://doi.org/10.1093/ismeco/ycae010
• Liu Y. et al. (2024) “Symbiodiniaceae and Ruegeria sp. Co-Cultivation to Enhance Nutrient Exchanges in Coral Holobiont.” Microorganisms 12 (6): 1217. https://doi.org/10.3390/microorganisms12061217
• Chen L. et al. (2024) “Low-Voltage Stimulated Denitrification Performance of High-Salinity Wastewater Using Halotolerant Microorganisms.” Bioresource Technology 401: 130688. https://doi.org/10.1016/j.biortech.2024.130688
• Balabanova L. et al. (2024) “LPS-Dephosphorylating Cobetia amphilecti Alkaline Phosphatase of the PhoA Family Divergent from the Multiple Homologues of Cobetia spp.” Microorganisms 12 (3): 631. https://doi.org/10.3390/microorganisms12030631
• Vázquez Rosas Landa M. et al. (2023) “Exploring Novel Alkane-Degradation Pathways in Uncultured Bacteria from the North Atlantic Ocean.” mSystems 8 (5): e00619-23. https://doi.org/10.1128/msystems.00619-23
• Tyson J. et al. (2024) “Prey Killing Without Invasion by Bdellovibrio bacteriovorus Defective for a MIDAS-Family Adhesin.” Nature Communications 15: 3078. https://doi.org/10.1038/s41467-024-47412-3
• Malfertheiner L. et al. (2022) “Phylogeny and Metabolic Potential of the Candidate Phylum SAR324.” Biology 11 (4): 599.