Ultrasound for Aquaculture and Net Fouling
ALGAEFREE’s Focus: Reducing Net Cleaning and Controlling Salmon Lice since 2006
Year 2006
Our History and Where It All Began:
Our First Ultrasonic Transducer for Salmon Farming Was Invented in Norway
Back in 2006 by Norwegian Inventor and ALGAEFREE CEO Odd Rolfsen
In 2006, ALGAEFREE conducted its first successful major salmon farming net trial in
Norway in collaboration with the VAL Aquaculture School.
This photos was taken during the first salmon-farming trial conducted in
2014 for Marine Harvest in Norway – now Mowi:
Cut Chemical & Maintenance Costs!
24–60 Month Rent-to-Own
PICTURE FROM SALMAR INSTALLATION 2019.
TEST RESULTS 48% LESS NET CLEANING WITH ALPHA 4-WAYS!
WANT TO POTENTIALLY SAVE APPROXIMATELY US$52,000 PER CAGE, PER YEAR?
We’re ready to design, deliver and provide outstanding service and support.
We also have a dealer in Norway – see CONTACT US for details.
Graph from SalMar Test 2019
June 1 – 30 Algaefree ultrasound cage 1 Flushing. All other cages 2 Flushes
July 1 – 31 Algaefree ultrasound cage 1 Flushing. All other cages 3 Flushes
August 1 – 22 Algaefree ultrasound cage 0 Flush. All other cages 1 Flush
ULTRASOUND REDUCES NET CLEANING BY 50%
AND REDUCES STRESS ON FISH!
SAVE THOUSANDS PER CAGE, EVERY MONTH WITH ULTRASONIC NET CLEANING.
Laser vs Continuous
ultrasound for Salmon-Lice control:
Warm-water treatment vs Continuous
ultrasound for Salmon-Lice control:
HOW ULTRASOUND ELIMINATES SALMON LICE
The 8-step Ultrasound proses for cleaning fish-farm nets!
VEOLIA 100m x 100m IRRIGATION DAM
93% PROVEN RESULTS — SEE THE DIFFERENCE IN PICTURES
READ VEOLIA’S OUTSTANDING TEST RESULT
Veolia Ref Algae Ultrasound Trial – 98% algae cell reduction
SEE FISH FARMING SUCCESS STORIES FROM AROUND THE WORLD
SALMAR HATCHERY
ALGAEFREE Alpha 4-ways at salmon hatcheries and smolt production
ALPHA 4-ways in a trickling finger sump in the Hatchery
HEALTHY SALMON SURVIVE AND GROW FASTER
SalMar at Finnsnes, Norway, began testing 4 ALPHA 4-WAYS ultrasound transducers at its juvenile fish facility in 2020.
The results quickly demonstrated the benefits of ultrasound for fish welfare and cleaner conditions.
After only a few weeks, SalMar observed that the salmon’s gills were clean.
The results exceeded expectations and gave SalMar the confidence to expand the system.
Later in 2020, SalMar invested again, purchasing an additional 8 ALPHA 4-WAYS transducers.
THE RESULT: 100% CUSTOMER SUCCESS — EXCEEDING EXPECTATIONS
From an initial 4-unit trial to an additional 8 transducers — SalMar’s reinvestment speaks for itself.
Independent testing conducted by King Abdullah University of Science and Technology KAUST Beacon, demonstrated
a 70–75% reduction in algae and slime buildup on fish farm nets at TARAWAR Fish Farm, highlighting the
technology’s strong antifouling performance and its potential to significantly reduce maintenance requirements.
Three SunSonix solar panels and six ALPHA 4-way transducers were successfully deployed in January 2024 for aquaculture testing at THARAWAT Fish Farm in the Red Sea. Each solar unit is supplied fully pre-assembled with integrated batteries for easy plug-and-play installation.
After three months, the net remains almost completely free of biofilm and algae growth. Biofilm colonization and algae buildup have decreased, and the frequency of net cleaning has been reduced by approximately 75%.
ALPHA ULTRASOUND TEST FOR HUON IN TASMANIA 2022
OUR SALMON FARM TRIAL IN TASMANIA SHOWS THE DIFFERENCE WITH ALPHA AFTER 8 WEEKS
Our Tasmania trial recorded a 73% reduction in net cleaning.
ULTRASOUND is designed to control algae and biofilm, helping reduce the need for costly net cleaning.
Algae-related gill and breathing problems were also reported to have resolved during the trial.
STILL CLEAN AFTER 28 DAYS — WITHOUT NET CLEANING!
The pictures show the fish farm net 28 days after installation, with no net cleaning during this period. While the surrounding net remains remarkably clean, some fouling is visible on the transducer and rope.
The rope’s rough surface can trap biofilm and organic material more easily than the surrounding net. Material can also accumulate around the transducer’s edges, fittings and attachment points.
SIMPLY WIPE THE TRANSDUCER AND ROPE WITH A SOFT CLOTH ONCE A MONTH
TRANSDUCER ANTIFOULING PROTECTION — AVAILABLE SINCE 2023 TO HELP EXTEND CLEANING INTERVALS
20 EXTRA DAYS WITHOUT NET CLEANING
ALGAEFREE EXTENDS THE CLEANING INTERVAL FROM 41 TO 61 DAYS
The control pen reached the net cleaning trigger score of 4 after 41 days, while the trial pen reached the same score after 61 days. Day 59 was excluded because the initial score of 4 was reassessed as 3 by the net cleaning ROV staff.
The trial pen equipped with ALGAEFREE ultrasonic units achieved a net cleaning interval of 61 days, compared with 41 days for the control pen.
Murray Darling Fisheries — Wagga Wagga, NSW
ALPHA 2-way ultrasound units are used to reduce algae growth and cage fouling in freshwater grow-out ponds.
MURRAY DARLING TRIAL REPORT:
We have seen strong results from a recent trial using a small ALPHA 2-way ultrasound unit from ALGAEFREE to reduce algae growth and cage fouling in a freshwater grow-out pond in the Riverina region of Australia.
During the previous season, the cages required cleaning every 2–3 days to maintain water flow and oxygen levels. After each cleaning, the fish stopped feeding for a full day. This frequent cleaning contributed to increased labour costs and reduced fish growth.
This season, an ALGAEFREE ultrasound unit was installed in the pond. The cages remained clean for three months without any cleaning. This reduced labour requirements and improved fish growth, resulting in a shorter grow-out period.
To assess the performance of the ALGAEFREE ALPHA 2-way ultrasound unit, it was switched off after three months of operation. Ten days later, the cages were completely blocked by fouling and required cleaning.
A single ALPHA 2-way ultrasound unit was used for the trial.
ROCKY POINT — Woongoolba, QLD, AUSTRALIA
Rocky Point breeds beautiful cobia and has experienced significant algae problems in its freshwater pond.
Peter from Rocky Point Aquaculture inspects the ALGAEFREE ALPHA ultrasound unit.
They installed an ALPHA 2-way ultrasound unit in 2019, and their Processing Manager, Peter Cummings, told us the results were amazing! Following this success, they invested in additional ALPHA 2-way units in 2020, placing them on different sides of their pond.
The net before installation of the ALPHA ultrasound system
BEFORE ALPHA INSTALLATION: The fish net was heavily fouled with mussels.
AFTER ALPHA INSTALLATION: There are almost no mussels on the net.
Trinity Bay Barramundi – Cairns, QLD
Saltwater Cages
Clean cage after 4 weeks with ALPHA ultrasound 1 week after the ultrasound was switched off
Australian Bay Lobster Producers Ltd
Tweed Vally Way, Chinderah NSW AUSTRALIA
2017
In 2017, we supplied Australian Bay Lobster with two ALGAEFREE ALPHA Ultra Q 4-way ultrasound systems for a trial. They had previously tested other methods without success to eliminate the biofilm associated with severe sponge growth in their water tanks. Although initially sceptical, they accepted our trial offer.
After just 21 days of continuous operation, the biofilm was completely eliminated, resolving the sponge problem in the treated system.
2018
In 2018, ABLP installed five ALGAEFREE ALPHA Ultra Q 4-way ultrasound systems. These successfully restored water quality by controlling biofilm, algae and bacteria and resolving extensive sponge infestations in the water tanks.
The results are documented in five independent reports prepared by ABLP Design Biologist Huw Griffiths, supported by before-and-after photographs.
2022
In 2022, Australian Bay Lobster purchased another ALGAEFREE ALPHA 4-way ultrasound system, demonstrating their continued confidence in the technology’s performance and reliability.
2016
2016 Milestone: ALGAEFREE ALPHA 4-way Ultrasound System Installed in a Norwegian Salmon Farming Cage in China
During construction, 25 ALGAEFREE ultrasound transducers were strategically installed to provide continuous biofouling control and support optimal operating conditions.
ALGAEFREE played a key role in SalMar’s construction of the world’s largest offshore fish farming facility in China, with our advanced ultrasound technology integrated into the facility’s design.
ALGAEFREE CEO Odd Rolfsen at the construction site of the Norwegian Ocean Farming salmon cage in China, supervising the installation of 25 ALGAEFREE ultrasound transducers in 2016.
2006
Our First Successful Salmon Farming Net Trial — Norway, 2006
In 2006, ALGAEFREE conducted its first major salmon farming net trial in Norway in collaboration with VAL Aquaculture School.
To evaluate our ultrasound technology, VAL Aquaculture School built two salmon farming net cages without antifouling coatings specifically for the trial. The objective was to determine whether ultrasound could prevent biofouling and algae growth without traditional antifouling coatings.
The results demonstrated ultrasound’s potential to help keep fish farming nets clean. Wider commercial adoption could reduce maintenance costs and reliance on antifouling coatings, supporting more sustainable salmon farming.
The Remarkable Results of Ultrasound in a Fish Farming Cage After Six Months
After just six months of continuous operation, our ultrasound technology delivered outstanding results,
significantly reducing biofouling and demonstrating its effectiveness in maintaining cleaner fish farming
cages without the use of chemicals or antifouling coatings.
How Ultrasound Fights Salmon Lice
Ultrasound is used as a method to combat salmon lice in fish farming cages by disrupting the lice infestation early in its development.
The technology, which has been under development for ten years, can reduce lice infestation by up to 60 percent,making it a preventive tool in the fight against the parasite.
The system consists of ultrasound units that are easily mounted in the cage.
Ultrasound Fights Salmon Lice
Preventive method: Ultrasound equipment is used as a preventive measure to stop the lice at an early stage of its life.
Interrupting the life cycle: The goal of the technology is to disrupt the salmon louse’s life cycle so that it cannot attach and reproduce.
Reduced infestation: Tests show that the technology can reduce the amount of salmon lice by around 60 percent.
Complementary method: Although ultrasound reduces lice infestation, it still serves as a supplement to other methods used in combating salmon lice.
Ultrasound for Lice Control
Ultrasound and Lice Detachment: Ultrasound waves can cause disruption in the attachment mechanism of salmon lice, making it harder for them to cling to the fish, leading to a decrease in lice population over time.
Ultrasound’s Impact on Lice Movement: The ultrasonic sound waves disorient salmon lice, disrupting their movement and feeding behavior, which can prevent them from effectively attaching to or infesting the fish.
Ultrasound as a Repellent: Salmon lice tend to avoid areas treated with ultrasound, as the sound waves interfere with their sensory systems, acting as a deterrent to their attachment and survival.
Ultrasound for Lice Control: By emitting high-frequency sound waves, ultrasound can damage the sensory organs of salmon lice, interfering with their ability to find and infest the fish, resulting in reduced lice numbers.
Ultrasound’s Effect on Lice Reproduction: The application of ultrasound waves can interfere with the reproduction and egg-laying process of salmon lice, limiting their ability to reproduce and helping to control the overall population.
The Benefits of Ultrasound in Fish Farming Go Beyond Fish Welfare
Our ultrasound technology not only improves fish welfare but also helps keep nets cleaner, reduces
biofouling, lowers maintenance costs, minimizes the need for antifouling coatings and chemicals,
improves water flow and oxygen exchange and supports more sustainable aquaculture operations.
All ALGAEFREE SYSTEMS are 100% environmentally and fish friendly!
It is a onetime investment!
It kills algae growth that is already stuck on the net!
Prevents new algae growth!
Achieve massive cost savings to your maintenance budget yearly
ALPHA SYSTEMS are useful wherever there is fouling problems!
Tested for over 6 years with amazing results!
Electronics work year after year!
Cheapest ways of antifouling- ever!
Easy to install!
No maintenance!
The system is flexible!
Heavy Duty transducer
The Effects of Ultrasound Algae Control Technology on Fish Health and Welfare
As of June 16, 2022, through the published (Taylor & Francis) report by Cornell University, HBS Ultrasonic technology is the only
peer reviewed, American made, ultrasonic algae remediation product on the market. This report proves both in field and lab
tests that our technology does not detrimentally affect fish. Abstract Getchell RG, George E, Rice AN, Malatos JM, Chambers BM,
Griefen A, Nieder C, Rudstam LG. 2022. Effects of ultrasonic control devises on fish. Lake Reserv Manage. 38:240–255.
Harmful algal blooms (HABs) can have serious impacts on both ecosystem services and human health, and several mitigation
techniques have been developed to control them. Ultrasonic sound sources can disrupt developing algal mats, causing
concern that the acoustic energy emitted from these devices may have deleterious health or behavioral effects on nearby fishes.
We conducted field and laboratory studies on the effects of ultrasonic control devices on resident fishes. Field observations in
Oneida Lake, New York, of the behavioral response of fish to the ultrasonic sound were conducted in shallow water using
line transects, and in deeper water using hydro acoustics. No avoidance behavior was detected in either shallow or deep
water while the ultrasonic devices were operating. Under controlled laboratory conditions, 7 recreationally or ecologically
important fish species and local wild tadpoles were exposed to sound produced by the ultrasonic control devices for a 2 week period.
No behavioral effects were noted while fish and tadpoles were monitored during the exposure interval. Finally, no significant
or harmful histological or morphological alterations to the skin, fins, gills, or internal organs were observed on either fish
or tadpoles when specimens were examined after the 2 week exposure period.
ULTRASOUND PUBLICATIONS
https://www.researchgate.net/publication/279499297_The_effectiveness_of_chemical-free_water_treatment_system_combining_fibre_filters_ultrasound_and_UV_for_fish_farming_on_algal_control
ULTRASOUND KILLS SALMON LICE
https://patents.google.com/patent/WO2017044985A2/en
Algae Toxins in Pond Aquaculture
https://thefishsite.com/articles/algal-toxins-in-pond-aquaculture
As of June 16, 2022, through the published (Taylor & Francis) report by Cornell University,
HBS Ultrasonic technology, is the only peer reviewed, American made, ultrasonic algae remediation
product on the market. This report proves both in field and lab tests that our technology does not detrimentally affect fish.
Abstract
Getchell RG, George E, Rice AN, Malatos JM, Chambers BM, Griefen A, Nieder C, Rudstam LG.
2022. Effects of ultrasonic control devises on fish. Lake Reserv Manage. 38:240–255.
Harmful algal blooms (HABs) can have serious impacts on both ecosystem services and human health, and several
mitigation techniques have been developed to control them. Ultrasonic sound sources can disrupt developing algal mats, causing concern
that the acoustic energy emitted from these devices may have deleterious health or behavioral effects on nearby fishes. We conducted
field and laboratory studies on the effects of ultrasonic control devices on resident fishes. Field observations in Oneida Lake, New York,
of the behavioral response of fish to the ultrasonic sound were conducted in shallow water using line transects, and in deeper water
using hydroacoustics. No avoidance behavior was detected in either shallow or deep water while the ultrasonic devices were operating.
Under controlled laboratory conditions, 7 recreationally or ecologically important fish species and local wild tadpoles wereexposed to
sound produced by the ultrasonic control devices for a 2 week period. No behavioral effects were noted while fish and tadpoles were
monitored during the exposure interval. Finally, no significant or harmful histological or morphological alterations to the skin, fins, gills,
or internal organs were observed on either fish or tadpoles when specimens were examined after the 2 week exposure period.
This illustrates where HBS technology works in frequency range and amplitude compared to other common
ultrasonic applications as well as maximum volume levels of dolphins and whales.