Fishmeal prices
up 80% YoY

Rising fishmeal prices are pressuring aquaculture feed suppliers to offer cheaper plant-based protein alternatives...with hidden consequences. Poorer digestibility. Negatively affecting fish health and FCRs.

Better fish health
and FCRs in RAS

The CarbonClear process improves your fish health and FCRs in RAS by binding and disabling the dissolved organic carbon by-products of digestion.

Plant protein comes
with a hidden cost

Fishmeal prices have nearly doubled in a year and global supply is at its lowest since 2016. Fish farmers are being forced to consider cheaper plant protein alternatives such as soybean meal. Plant proteins aggravate challenges already commonly experienced in RAS systems:

  • Dirty water
  • Poor fish growth & FCR
  • Excessive slime & mucus on gills
  • Off-flavour (muddy/earthy taste)
  • Fin erosion
  • Loss of appetite
  • Deformities
  • High mortality rates

Density effect: under the same conditions, these symptoms worsen at higher stocking densities.

Why?

Plant protein ingredients are less digestible, which exaggerates dissolved organic carbon (DOC) build-up in intensive aquaculture systems, especially RAS.

Read the Independent Review of Production Data and Claims

Our on-farm trials have shown the symptoms above are a result of dissolved organic carbons (DOCs) accumulating in the system water. As they accumulate, they quietly degrade water quality, fish health and ultimately fish growth performance.

Digestive metabolites produced in the fish gut and the system biofilm build up quickly in RAS water due to low water replacement rates. They accumulate as a mixture of many different types of DOC molecules smaller than 0.45µm. These organic compounds are re-absorbed into the fish flesh via the gills and accumulate to the extent that they give it an off-flavour. The compounds also seem to negatively affect fish physiology and endocrinology, harming their health and growth performance.

The compounds include Phenol, 1,3-Benzothiazole, 2,3,5-Trimethylpyrazine, 2-MIB, Geosmin and many others.

To date, their detection and management in RAS has been difficult due to the limited sensitivity of laboratory testing equipment. Human aroma detection (smell) is still the most effective tool used in off-flavour research today.

Read the research behind this

Based on the information provided, an independent technical review (October 2026) found that adding granulated activated carbon to feed is a scientifically plausible approach to reducing a broad range of organic compounds in RAS. The preliminary results and untested farm observations are encouraging, though require controlled, replicated and statistically relevant trials to establish the mechanism, specificity and efficacy of compound adsorption as well as the nutritional effects.

Matteo Egiddi
Independent Researcher / Consultant (commissioned independent professional opinion)

Remove dissolved organic
carbons at the source

The CarbonClear process uses food-safe, custom-made, powderized activated carbon to bind and remove dissolved organic carbons in a fundamentally more effective way.

1
Activated carbon binds dissolved organic carbons
Activated carbon is a proven toxin binder widely used to capture and disable dissolved organic compounds.
2
We put it in the feed
The CarbonClear process involves infusing powdered activated carbon directly into the feed pellet. This means binding and disabling happens at the source, inside the fish’s gut, before the DOCs have the chance to be released into the environment.
3
The activated carbon is milled to a fine powder
To work inside a feed pellet, the carbon is ground to a fine powder (PAC - Powdered Activated Carbon). Finer particles adsorb far faster, which matters because the carbon has only a short window inside the fish’s gut. It also disperses evenly through the pellet and stays suspended in the water once excreted.
4
It keeps working after excretion
Once excreted, the activated carbon continues adsorbing dissolved organic carbons and phenolics from the surrounding water, right up until it’s captured by standard mechanical filtration (typically a drum filter).
5
Everything gets removed together
The activated carbon and the organic compounds bound to it are the same physical particles. Mechanical filtration removes both in one step, no separate treatment stage required.

AMT Popular Article Archive

Think this could be
affecting your system?

Here’s how to find out and what to do about it.

1

Test for dissolved organic carbon in your systemTest for DOC in your system

Send a water sample to your closest laboratory and ask them to test for dissolved organic carbon.

How to test your water

2

Try it

You have two options.

Ask your feed supplier

If you use an established international feed supplier, it is likely they already know about CarbonClear. Reach out to them to find out more. Introduce us if not and we’ll guide them through the process.

The CarbonClear process is protected by international intellectual property rights agreements.

Speak to us directly

If you want advice, further information or exclusive licensing for product development in your area, please reach out either over WhatsApp or by filling out the email form below.

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Enquiry submitted. You’ll hear from us shortly.

Our team

Teagan Bok
Managing Director
Teagan Bok

Teagan leads AMT’s day-to-day operations, working directly with RAS farmers to bring CarbonClear to you.

Lawrence Grant
Co-Founder & Lead Scientist
Lawrence Grant

Lawrence leads the scientific development behind CarbonClear, drawing on 15+ years of experience and research into phenolics, dissolved organic carbons and their impact on recirculating aquaculture systems.

Andre Bok
Co-Founder
Andre Bok

Andre co-founded AMT, using his 30+ years of RAS operational experience to shape the CarbonClear process. (Non-Executive)