Ozone: an efficient water treatment for Aquaculture

Have you considered how ozone can improve aquaculture water quality?

Applying ozone to aquaculture water treatment is a fantastic option to keep a healthy environment in the aquarium leaving no residual. With an ozone generator, it is possible to have an aquaculture water quality monitoring system, while treating the water.

So, how can ozone be so efficient in your aquarium’s water treatment? Read more below!

In re-circulation aquaculture systems (RAS), particles such as fish feces, unconsumed feed, bacteria and algae can cause several problems, as they end up harboring pathogens that will physically irritate the fish and, after decomposition, release ammonia and consume oxygen from the water.

The use of ozone in the re-circulating water system in aquaculture allows the user to benefit from a greater flexibility in site selection, reduced water usage, substantially improved water quality and reduced level of waterborne diseases.

Water quality depends on several factors and directly influences the productivity of the systems. So, let’s look at some key factors:

  • Concentration and time

The effectiveness of disinfection increases with the concentration and duration of exposure to an antibacterial. Therefore, increasing the duration and / or concentration of ozone reduces the burden of the pathogen, but has negative effects on animals, so the concentration and duration of exposure to ozone has to be studied case by case, varying from species to species.

  • Temperature

Directly proportional to the rate of a chemical reaction and will accelerate oxidation and thus the effects of ozone over a given time period and concentration.

  • Species and life stage

Within taxonomic groups, different species can show contrasting tolerances to ozone. Optimal ozone treatment may also vary inside particular life stages.

  • Organism size

Species with a larger egg diameter experience a better hatching rate, after ozone exposure. However, any correlation between size and tolerance may simply be a coincidence or related to species.

  • Genetics

Environmental differences impact on phenotype (tolerance to ozone or oxidants) within species, however, genetic (family or brood) differences may also be an influencing factor.


Water quality and salinity.

The highly reactive nature of ozone means that it decomposes to free radicals and other ozone derived chemical species, leaving ‘residual’ dissolved ozone.

Additional contaminants that react with ozone, such as particulates, total organic carbon load, bicarbonates and carbonates, contribute to the ‘ozone demand’ of a system, effectively competing for ozone and reducing the amount available for pathogen inactivation, which will improve animal physiology and growth.


The use of ozonated water is increasingly common and can be used in aquariums, marine tanks and zoos, where it will safely remove any microbes or fungi that cause disease, without the need to use chemicals.

  • Removes fine solids (particles from 1 to 30 microns) and colloidal particles (particles from 0.001 microns) which, due to their small size, pass through other separation methods and remain in suspension, impairing the nitrification of the bio filter, stressing fish populations – the ozone removes the fine and colloidal solids that cause microflocculation, facilitating filtration and sedimentation;;

  • Removes dissolved or refractory organic compounds that accumulate due to feeding, water changes and solids removal rate, changing the color of the water (it takes on a characteristic tea-like color), stressing fish populations and reducing the efficiency of nitrification of the bio filter – ozone removes dissolved organic compounds, oxidizing products that are more easily nitrified.

  • It removes nitrites, which accumulate depending on the intensification of production and the increase in organic loads.The greater the organic loads, the greater the ability of the bacteria that process ammonia into nitrite (Nitrossomas spp) over the bacteria that process nitrite into nitrate (Nitrobacter), thus increasing nitrite levels which, when high, can be toxic for the fish.

  • The disinfection of effluent waters used in fish colonies is one of the crucial factors to stop the transmission of exotic diseases and facilities must reduce exposure to pathogens introduced via source water, and wastewater must also be disinfected before discharge to the environment. Ozone can effectively inactivate a broad spectrum of bacterial, viral, fungal, and protozoan fish pathogens.


  • It has the power of disinfection that will reduce the spread of diseases;

  • Removes dissolved organic compounds (DOC);

  • It allows the micro-flocculation and oxidizes the organic matter;

  • Removes fine solids and destabilizes colloidal particles;

  • Removes nitrates;

  • Removes pathogens and toxic compounds;

  • Reduces water consumption by increasing water recirculation rate;

  • Improves the efficiency of the biological filter and particles;

  • Disinfects water;

  • Reduce odors, improving water clarity and quality;

  • Faster and better-performing growth rates;

  • Superior Environmental Control Standard;

  • Leaves no harmful residues;

  • Reduces unpleasant fish and seafood flavors;

  • Safe – ozone is certified as organic and it has the FDA and USDA approval  as allowed food contact substance;

  • Overcomes Other Treatment Processes.


Published: 2023

EMMANUEL I. EPELLE, ANDREW MACFARLANE, MICHAEL CUSACK, ANTHONY BURNS, JUDE A. OKOLIE, WILLIAM MACKAY, MOSTAFA RATEB, MOHAMMED YASEEN | February 15th | Ozone application in different industries: A review of recent developments

Published: 2019
Published: 2017

College of Agriculture and Life Sciences, Virginia Tech | Ozone Application in Aquaculture

Published: 2016

ADAM POWELL, JACOB W.S. SCOLDING | August 1st | Direct application of ozone in aquaculture systems

Published: 2011

WALTER J. BLOGOSLAWSKI, MARY E. STEWART | September 22nd | Some Ozone Applications in Seafood

ALEX A. GONÇALVES (Ozone: Science and Engineering), GRAHAM A. GAGNON | September | Ozone Application in Recirculating Aquaculture System: An Overview

Published: 2010

LIZANEL FELICIANO, JAESUNG LEE, JOHN A. LOPES, MELVIN A. PASCALL | May 3rd | Efficacy of Sanitized Ice in Reducing Bacterial Load on Fish Fillet and in the Water Collected from the Melted Ice

BEHROUZ MOSAYEBI DEHKORDI, NEDA ZOKAIE | 2010 | Extension of Fish Shelf Life by Ozone Treatment

Published: 2009
Published: 2008

NESTOR G. RAMOS, JAMES F. RING | July 23rd | The Practical Use of Ozone in Large Marine Aquaria

Published: 2002

Scientists at the North Carolina State University | March 26th | Researchers Find New Use for Ozone — enhancing the freshness of seafood

Published: 1999

PETER MAIRS, BARRY NASH, BARBARA BLAKISTONE, JAMES YUAN, GREG BOLTON | 1999 | Evaluation of ozone as a disinfectant agent to enhance quality and extend the shelf life on raw, vacuum-packed fish

Published: 1995
Published: Others

ITALY – Health Ministry | Scientific Validations of Ozone Use