Ultrasonic Antifouling Ltd

“Hull protection specialist for the prevention of underwater fouling"


Ultrasonic Antifouling Ltd provide a highly effective method, using the UltraSystem to prevent bio-film and algae growth on a yacht’s hull and sea chest system. The UltraSystem is one of the most advanced ultrasonic antifouling systems on the market

Main contact

Address: Arena Business Centre, Holyrood Close Poole, United Kingdom BH17 7FJ

Tel: +44 (0)12 02 60 61 85

Mob: +44 (0)75 90 35 60 00

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Ultrasonic Antifouling Limited are the pioneers of this electronic antifouling technology and the company that first introduced it to the boating market in 2007.

Alternative antifouling for yachts and superyachts

This state-of-the-art system uses low frequency, low power sound waves to destroy algae and bio-films and therefore prevent weed and barnacle growth.

Ultrasonic Antifouling Ltd has now introduced its new UltraSystem PowerPlus control unit taking ultrasonic antifouling protection for superyachts to a whole new level.

They are the world leader in ultrasonic antifouling technology for the prevention of underwater fouling and are able to offer a solution, which is both environmentally friendly and very cost effective.

Benefits of using the UltraSystem

Sea Chests fouling

- Maintain water flow to essential on-board systems
- Reduce maintenance and cleaning
- Save on the use of expensive, corrosive and harmful dosing chemicals

Hull fouling

- Maintain hull speed and reduce passage times
- Reduces fuel consumption by up to 30% - a massive saving in fuel bills
- Reduce the frequency of dry docking and paint application
- Easy installation and a high level of protection against fouling

A recent report by the British Navy states "that it can take up to 30% more fuel to push a dirty hull through the water".

The UltraSystem is in successful use on many yachts worldwide. Suitable for both sailing yachts and motoryachts.

How does ultrasonic antifouling work?

The control box sends a variety of pulsed ultrasonic signals to the transducer, which in turn emits a series of low power, low frequency sound waves which are virtually inaudible to the human ear. The resonance within the hull and sea chest system creates a wall of moving water molecules over the entire submerged area of the hull or the inner surfaces of the sea chest components. The micro - environment which exists as a result, destroys algae, bio-films and barnacles so they don't attach themselves.

Their new PowerPlus system provides twice the output level compared to Series II providing the highest level of protection for superyachts on the market today.

The UltraSystem utilises proven, world leading technology to provide the best protection for yachts. Ultrasonic Antifouling Ltd are highly knowledgeable experts and market leaders in this field. So, to find out how they can provide the best configuration to fully protect your yacht just call the number above or visit their website.

Additional Information

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This has worked extremely well

, Chief Engineer of 41m to 50m JEMS - 07/10/2015-10:06
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The Ultrasonic antifouling system has worked extremely well for us. We fitted transducers on each of the sea chests and without exaggerating, we had zero growth since the install in February, intervals between cleaning heat exchangers has been significantly extended.


, Engineer of 31m to 40m S/Y Nilaya - 07/10/2015-09:37
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The Ultra 20 Dual systems have definitely been worth their weight on board the yacht ‘Nilaya’ over the last two years and the difference it makes to the growth on the bottom of the boat has been unbelievable.

Very Impressed

, . Cypriana - 07/10/2015-09:35
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We have just recently lifted “Cypriana” and I am very impressed with the result compared to what I had on my previous yachts in previous years.

In previous years we have had to send a diver down to scrub the surface before our 120 mile travel to the lifting dock, since speed would have been cut down by 4 mph, and we would get vibrations due to the growth on the shaft. We had no reduction in speed and there was not much work left for the diver, so we just went straight ahead this year.

A clean hull

Wee Hopscotch - 04/03/2014-16:34
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I fitted an Ultra10 system to my Nelson 29 motor boat about 2 months after launching. The boat is kept in a marina berth in Poole harbour. At the time the unit was fitted growth had already begun to form on the waterline. After the unit had been in place for about 3 months I slipped the boat prior to a cruise. I was very pleased to find that the only growth was a fine slime, which was presumably that which was there before fitting. The trim tabs had algae on the top but not the underside and there was some around the stern but only at the waterline. It was quite apparent that the unit was having a very beneficial effect and had prevented further growth from forming. I am confident that the unit will keep algae at bay now that the hull has been power-washed and the unit is in operation on a clean hull.


, Yacht, Why Knot Why Knot - 04/03/2014-16:33
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A boat moored next to “Why Knot” from 25th June until 10th July developed growth of shell animals and algae but the hull of “Why Knot” remains totally clear. Even the paddle wheel of the speedometer no longer needs clearing when, previously this was required regularly. The situation remained the same right through to September clearly showing the effectiveness of the Ultrasonic antifouling system.

Proved effective

, N/A Crouch - 04/03/2014-16:30
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Ultra system has considerably reduced the infestation of barnacles and that the performance of the boat did not deteriorate significantly during the season. The system has proved to be effective in discouraging barnacles and other animal marine fouling.

Efficiency is at its highest.

, Jersey CI Fox Marine Services - 04/03/2014-16:27
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In the Channel Islands we suffer from heavy fouling of the hull and have to lift the boat up to 3 times a year for power washing and re-coating the conventional anti-foul paint.

With this system we have found that it still requires anti-fouling but just once a year and has eliminated the need to lift the boat out during the season saving valuable time and money.

The system is easy to install even for the average person and with less growth the performance is not decreased and fuel efficiency is at its highest.

Could not believe our eyes

, . Cariad 2 - 04/03/2014-16:24
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We could not believe our eyes as Cariad 2 was lifted clear of the muddy River Exe water. Not a trace of shell or weed fouling and only a slight slime just below the waterline which was easily removed by our domestic Karcher water jet. Thanks to your product we have saved at least a morning’s hard work and a lot of back ache.

No evidence of excessive weed

, Owner Orion - 04/03/2014-16:22
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I had a diver down in late December two months after fitting the system. There was no evidence of excessive weed only one barnacle on the prop 40 minutes and the hull was clear. Very satisfactory. The boat had been antifouled aprox 18 months prior by the previous owner and cleaned and washed twelve months prior when the boat had been slipped for survey .

There is an audible noise at night as out of necessity the system is fitted beneath my bunk however it is not loud enough to cause either my wife or I to need to switch it off at night.


Owner - 04/03/2014-16:20
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I have a Bertram 35 and we fitted the device in August. The boat was previously antifouled in Sept 2007. At the time of fitting the unit we had weed on the waterline and other boat owner’s near us had divers cleaning their hulls.After a month we took the boat out and when we came back all the weed was gone. Subsequently we slipped the boat in Sept and the hull was clean. The shafts and trim tabs had molluscs on but they were already attached from last year.

Working very well.

, Gosport, UK Raffles - 04/03/2014-16:16
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About 18 months ago not long after purchasing my boat I was bemoaning the fact that I had spent the last 2 days cleaning the hull, props & shaft to prepare the hull for antifouling. We were having a bacon butty and a cup of coffee down at Davis’s Boatyard when one of the other boat enthusiasts introduced me to David Sothcott who had this “Ultrasonic Antifoul Unit”. It sounded almost too good to be true but the thought of not having to spend time & £ every year getting the bottom of the boat clean was appealing. I purchased a mains powered unit and installed it, in the wrong place, but after getting advice from David and repositioning the unit we have had almost no weed growth at all. The boats on either side of us in the marina have to regularly scrub the waterline and really need a full clean & antifoul each year. With the added benefit of fuel efficiency the unit will have paid for itself in the first year. The product is working well.

Over 2 years in the water

, Owner Birchwood 49 - 04/03/2014-16:15
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We are delighted with the Ultrasonic system that we fitted to our boat over 2 years ago. It has performed even better than we had hoped! Our boat has remained on her marina berth for over 2 years without being moved at all (due to illness & family commitments) & we have had 2 short cruises in the last month. When she was lifted there was only a very slight film on the hull which washed off incredibly easily & some weed along the waterline, which under normal circumstances we would have scrubbed off. There was a small amount of the dreaded “worm” on the rudders, props & trim tabs, but Chichester is notorious for worm infestation & the rest of the hull was completely clear.

Very pleased

Ministry of Defence - 04/03/2014-16:13
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Three LCVP MKIV landing craft were each fitted with three transducers, protecting not just their hulls but also their sizeable stern gear.

Earlier this year, the Australian Customs & Border Protection Service also installed Ultrasonic Antifouling technology on one of its vessels tasked to patrol the coast off the country’s Northern Territory.

We are very pleased that these organisations are using our products and have gained such success from them.

Great results

, TV personality N/A - 04/03/2014-16:10
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With time a rare commodity, I simply want just get on the water and have time in my Ribquest RIB without the hassle of maintenance and seasonal antifouling disturbing my rare time off.

Having tested many anti-foul products, I have seen the Ultrasonic Antifouling system work over the past 4 months and barnacles, I hope they are a distant memory.

When she was lifted

, Owner Venture II - 04/03/2014-16:08
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Waterline area only saw a small line of growth which can be expected where the water is lapping….ultrasound does not work in air! From the Ultrasonic process, this growth is very soft and easily removed with a sponge.

Area where shaft exits the hull: The isolated bearing flange and shaft only show a small amount of growth, the close proximity of one transducer has provided a good benefit to these parts.

One of the stabilisers: The rigid attachment to the hull has allowed effective resonance of sound onto the stabiliser keeping it clear of growth. Only a little slime was there which was very soft and could be rubbed off easily with no effort.

The face of the depth transducer: the sealant around this transducer isolates it from the sound resonating throughout the hull.

Converted to ‘ultrasonic’

, Owner Wanderer - 04/03/2014-16:04
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I am the owner of a Westerly Centaur. For the last 10 years I have been scraping, rubbing down and applying antifoul paint every winter. The boat is kept in a salt water environment (marina) in the summertime for approx. 6 months, and out of the water on the hard for the winter.

I inadvertently mentioned ‘Ultrasonic antifouling’ in a family conversation last year, and much to my surprise got an ‘Ultrasonic 10′ kit as a Christmas present! I fitted the ultrasonic system last April, leaving the hull unpainted with the residue of the previous season’s antifoul paint still on, and the boat was put back in the water. The boat was lifted out last Tuesday and I was very pleased and relieved, to note that the hull was in excellent condition. The only signs of some growth were around the Prop and the Log.

Will keep you updated

, Chief Engineer Officer of 31m to 40m M/Y Metsuyan IV - 04/03/2014-16:00
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We were launched in early may and when I checked the strainers last week they were spotless. I think that is a very good result! I will keep you updated through the season with what we see, but so far it looks good.

What a great product!

, . Freyja - 04/03/2014-15:59
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I recently lifted ‘Freyja’ a 31ft Botnia Targa after 10 months in the water and I am extremely pleased with the results.

My main concern was the fouling on the two stern drives and whether the Ultrasonic System would help these, but I took the recommendation to install two transducers and can say that the drives were considerably better than they were previously after 6 months in the water.

The hull was incredibly clean, just some growth around the sides which I was told to expect. This would account for the fact that the boat had not lost any significant performance.


, . Topaz 37, Gigi II - 04/03/2014-15:57
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Normally the frequency to clean the hull of this vessel was up to 3 times a month, this is no longer needed. The vessel was launched in May 2010 and out hauled in June 2011 and the results were fantastic.

Never happened before!

, Potsdam, River Havel, Germany Fisher Catamaran- Catfish of Cheshire - 04/03/2014-15:54
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I bought my Ultra 20 system in mid-2009. In 2010 I launched her with the ultrasonic newly fitted and powered up, and I had been particularly careful to prepare the hull surfaces under the transducers to ensure perfect contact. I was impressed that the system was inaudible, except in the heads where some gentle ticking was just discernible through the shower grating – in fact a nice reminder for a few minutes each day that something other than me was doing all the hard work of antifouling! The summer progressed, and all I had to ensure was that the boat stayed connected to the shorepower in my absence.

Eventually the day came when I returned to the boat after a month’s absence, to discover that the lake water was up at 25C – and amazingly, that there was nothing more than a little slime and certainly no weed, not even on the waterline. Most remarkable of all were the tops of the stern platforms, which sit a couple of inches underwater. Usually by now their upper surfaces would be a carpet of weed, but they were completely clear. This had never ever happened before, not even after several coats of the most expensive antifouling paint.


, . S/Y Polished Manx - 04/03/2014-15:51
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I have been using it successfully for a second full season. First season I was 95% satisfied. 95% because my swing moored boat did not have sufficient battery capacity to keep it running.

I got in touch with you and one very important piece of advice came ­ ‘you don’t have to have Ultrasonic running during the night’, therefore I have installed a timer and set it up to work when the sun was up between 09:00 -17:00 and an extra battery which made me absolutely 100% satisfied. I know that the extra battery is an overkill and boats in marinas fortunate to be on AC shore power don’t need to bother, but I like my 100% assurance that I am OK.

Very impressed

, . Seadogz - 04/03/2014-15:46
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Over all we are very impressed. We have kept out fuel costs down, speed up and greatly reduced the man hours needed to keep the gel coat in shape (it’s more like man minutes now). And of course we don’t need to have a change of anti-foul every year or so which saves more money.
Thoroughly recommended if fuel efficiency and performance is an issue. We would fit it again without hesitation.

Halved my costs!

, Elan 333 Melody - 04/03/2014-15:44
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since installing an Ultrasonic antifouling system in my Elan 333, my antifouling costs have halved. Previously, I had always put at least two coats of antifouling on all surfaces below the water line, with up to four on the leading edges to ensure full protection. However, since installation I only apply one coat throughout with two or three where erosion is likely to be the greatest. At the end of a six month season at lift-out from my marina berth, the hull, fin and rudder have been completely free from marine growth just some light slime. The antifouling I use is seajet 033 Shogun and this in combination with the ultrasound system works very well where the sound can reach. I do get some fouling on an unprotected folding propeller and a little on my sail drive leg but that is not unexpected as the engine and sail drive are acoustically isolated from the rest of the hull by the engine mounts.Often I have been asked by friends how do I know that the sound is reaching all parts of the boat? It is an interesting question but one that can be quickly confirmed when the boat is laid up in the winter. My Ultrasonic Antifouling transducer is mounted on the centreline in the bilge midway between the trailing edge of the fin and the sail drive. All you need to do is switch it on and put your ear to the hull and you can hear the distinctive “clicks” if it is working properly confirming that there are no voids between the transducer, silicon grease and the hull. On my boat the clicking can be heard throughout the hull right up to the bow as well as at the tip of the rudder and at the bottom of its deep keel. I purchased my system, the ac powered version, when it was first shown at the Southampton Boat show in 2009. Since then it has more than paid for itself and significantly reduced the time and effort required to prepare the boat for the next sailing season.

Very satisfactory

, Owner Jeanneau NC9 - 04/03/2014-15:42
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I return to you to tell you that the Ultra 10 system is successful on my Jeanneau nc9 in Brest, except on the top of the flaps and top of the z-drive where they have some little algae. It remained in the water 10 months and no shells, the result is very satisfactory.

my recent experience

, Swedish Dealers Viking Yachting AB - 04/03/2014-15:41
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It was, unfortunately, due to circumstances beyond my control as they say, over a year between my last slip footage of Zephyr. 18-06-2012 I was out last year until 26-06-2013. So she had been in all winter. 446 running hours, she has gone over the period with an average speed of approximately 20 knots. Mostly cruising around 25-28 knots with peaks around 35 knots.

As shown on the attached photos, I have not any growth of barnacles and only a little green algae in the water line, the trim tab edges and drive. This green algae has not resulted in any increased fuel consumption during the period and dropped slightly at the end of the period.

The unit has been in operation for the entire period and I am becoming more and more convinced of the good it does.

4 years in the water

, Owner Arabella - 04/03/2014-15:39
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After 4 years in the water I was amazed! I intended to keep her in the water for as long as possible and really see what the system could do with an old coating of antifoul paint. It should be realised that I do not sail her very often, perhaps only 3 or 4 times a year, so the hull does not receive a beneficiary wash to help reduce the build up. Then there are the few occasions when the shore power connection has been lost and the system has not been working for several weeks. I could see the difference straight away with new algae growth but the system seems to sort this out after a few weeks. It’s impressive to say at the least, to see the ultrasonic system keep a hull this clear for nearly four years in the water while using an old paint, which would have lost its antifouling effects a long time ago. Let’s see how things fair in the next few years now the hull has been cleaned off.

Thanks and again well done on producing an economical and effective system.

, Hong Kong S/V Miss Behave - 04/03/2014-15:36
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This year was one of the most severe for barnacle and sea worm in our bay yet we removed less than a half a cup of small barnacles from the hull and less than half a gallon bucket of growth from the keel and rudder. The remainder of the hull was covered in a mud like slime that easily came away with a light touch of the finger.

We are thoroughly delighted with the results and can recommend the system to anyone with a suitable hull. We will now go on to a 2 year trial with the intention to sail to Australia via the Philippines, Palau, New Hebrides and Vanuatu.

Thank you for a great product!

, Owner Windy Ghibli 28 - 04/03/2014-15:34
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I have one of your Ultra 10 series 2 ,serial no flt120711049 fitted to a Windy Ghibli 28. After her 1st season she came out for a scrub having been in the water from Easter to September, I could not believe how little fouling there was on the hull, only a few barnacles at the very front of the boat forward of the bow thruster.

To put things in perspective the out drives were unrecognisable under a carpet of weed etc. Please hurry up and design something for them. The yard staff were also amazed at the cleanliness of the hull and to be fair the whole pressure washing of the whole boat including drives and tabs took no more than 10 minutes to completely clean back as original.