Ultrasonic antifouling

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BrentwoodBayliner

Veteran Member
Joined
Apr 25, 2020
Messages
43
Location
Canada
Vessel Name
Bonita Rose
Vessel Make
1981 Bayliner 3270
My dockmate here on Vancouver Island has a Tolly 36 and recently installed an ultrasonic system which claims to inhibit underwater growth on the hull by introducing a series of ultrasonic vibration pulses into the hull 24/7. A couple of 'pucks' are glued to the inside of the hull and wired into a central 12v sending unit.

It claims to disrupt growth at the cellular level by basically 'shaking' the little critters so they can't settle in.

The makers are very clear this will not remove existing growth and will not work if it is installed on an already overgrown hull. It has to be a clean start.

My neighbour pulled the boat out almost a year ago for cleaning and fresh paint and installing the units. So far it seems to be working really well - nothing growing.

Current price is around US$1700 for 4 pucks and processor. Fairly easy DIY install. Not cheap, but if it allows him to go from an annual haulout to every second year, it wouldn't take long to pay for itself.

I can't find any previous mention of this on the Forum. Anyone tried it?
 
Here's a thread from a while back. "fastbttms" is a hull diver and will likely chime in with some of his usual FUD. Seems he lives to post on ultrasonic systems.

I reached out to HullShield and asked for a "twin study" where one hull of a catamaran has their system, the other does not. They said it was in the works but that was about 2 years ago. Nothing so far, just a lot of anecdotal claims. Until something more definitive comes along, I categorize it alongside Algae-X fuel magnets.

https://www.trawlerforum.com/forums/showthread.php?t=47771

Reading through the above thread, sounds like Syjos installed the system. Maybe he'll update on performance.

Peter
 
I know they installed this system on Delos and it was not deemed to work very well.
 
I can't find any previous mention of this on the Forum. Anyone tried it?

I have been reading threads about ultrasonic antifouling for 15 years. They seem to exactly match results of threads about CopperCoat.

It other words some say it works and some say it doesn't.

I too have been waiting to see a test on a multi-hull side by side test.
 
I have been reading threads about ultrasonic antifouling for 15 years. They seem to exactly match results of threads about CopperCoat.

It other words some say it works and some say it doesn't.

I too have been waiting to see a test on a multi-hull side by side test.

Any system that’s been around for 15 yeas and has generated no definitive data is probably a gimmick.
The boating world is hungry for an antifouling product that works well, so it would be extremely popular if it were indeed effective.
 
Any system that’s been around for 15 yeas and has generated no definitive data is probably a gimmick.
The boating world is hungry for an antifouling product that works well, so it would be extremely popular if it were indeed effective.


Exactly. If these worked, the people using them would be screaming from the hill tops telling everyone about it, just as people swear by stabilizers, Starlink, LFP batteries, and other things that make a real difference.
 
Here's a thread from a while back. "fastbttms" is a hull diver and will likely chime in with some of his usual FUD. Seems he lives to post on ultrasonic systems.

Guy goes back three years to dig up a 4-page, 76-post thread where I made three comments about ultrasonic systems :thumb:

I just call out BS when I see it. Did I do that to one (or more) of your excellent posts? :lol:
 
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After reading mixed reviews on hullshield I bit the bullet and installed 8 pucks on my boat last month. I hauled out in July 2023 and had 3 coats of anti foul paint applied. Given Tampa Bay warm waters historically I’ve needed to clean my hull at least every 3-4 weeks. I dived my hull after installing the system and cleaned the small amount of growth since haul out. I plan on doing a video review next month after 8 weeks since installation. Historically I’ve needed to do 10-12 cleanings per year, if the hullshield can cut this in half I’ll consider it a success. Will post a link here after doing the video.
 
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I plan on doing a video review next month after 8 weeks since installation.

Two issues (at least) with this kind of feedback:

1.- In two months, your brand new anti fouling paint will still be leaching its biocide at its absolute maximum rate. That being the case, one would expect that the bottom would be relatively clean, whether an ultrasonic system was in use or not.

2.- Since you supposedly do not have video of your boat's bottom with new paint and no ultrasonic system in use, we have no benchmark to tell how well the Hull Shield is working. So showing us a video of your 2-month old paint being used in conjunction with an ultrasonic system is really meaningless.
 
Two issues (at least) with this kind of feedback:

1.- In two months, your brand new anti fouling paint will still be leaching its biocide at its absolute maximum rate. That being the case, one would expect that the bottom would be relatively clean, whether an ultrasonic system was in use or not.

2.- Since you supposedly do not have video of your boat's bottom with new paint and no ultrasonic system in use, we have no benchmark to tell how well the Hull Shield is working. So showing us a video of your 2-month old paint being used in conjunction with an ultrasonic system is really meaningless.

Fair enough comments, I plan on keeping a running video log going forward. I clean my own hull when possible, as the saying goes, “if you want it done right do it yourself”. Last year I had been paying a diver to clean the hull and after 3 months I tried to take the boat out but had so much growth on the running gear that I had no thrust. To be honest I don’t know what the diver was doing for an hour underwater. Again, the objective is to get by on 5-6 cleanings per year.
 
Last year I had been paying a diver to clean the hull and after 3 months I tried to take the boat out but had so much growth on the running gear that I had no thrust.

So on an old bottom in Florida that you would typically clean 12+ times a year, you waited three months after service to take the boat out and it's the diver's fault that your running gear was foul? You have got to be kidding me! :lol:
 
Has the overriding "Be Nice" rule been abolished?
 
Has the overriding "Be Nice" rule been abolished?

Give fstbttms a break. He's prone to hyperbole and is a bit touchy about anything that might encroach on the need for a bottom diver. I'm sure he means well. Just can't help himself.

Peter
 
So on an old bottom in Florida that you would typically clean 12+ times a year, you waited three months after service to take the boat out and it's the diver's fault that your running gear was foul? You have got to be kidding me! :lol:

No these were monthly cleanings over a 3 month period. I took the boat out a week after the supposed last cleaning. No way an inch of growth in only a week. The funny thing is if the growth was so bad that the diver needed more time I would have gladly paid additional. Nope just kept collecting his fee and never said anything.
 
Everything I have read says ultrasound devices are not a substitute for bottom paid. Most ultrasounds devices say in the fine print that they help your bottom paint do it’s job better.

Fstbttms points out the lack of proper controls in most studies.
 
No these were monthly cleanings over a 3 month period. I took the boat out a week after the supposed last cleaning. No way an inch of growth in only a week. The funny thing is if the growth was so bad that the diver needed more time I would have gladly paid additional. Nope just kept collecting his fee and never said anything.

OK, thanks for clarifying
 
After reading mixed reviews on hullshield I bit the bullet and installed 8 pucks on my boat last month. I hauled out in July 2023 and had 3 coats of anti foul paint applied. Given Tampa Bay warm waters historically I’ve needed to clean my hull at least every 3-4 weeks. I dived my hull after installing the system and cleaned the small amount of growth since haul out. I plan on doing a video review next month after 8 weeks since installation. Historically I’ve needed to do 10-12 cleanings per year, if the hullshield can cut this in half I’ll consider it a success. Will post a link here after doing the video.


I'm looking forward to seeing your documentation on the efficacy of the system you installed! It will be nice to see factual, pictorial data.

In the absence of photographic evidence of what the bottom looked like after cleaning and applying three coats of bottom paint, I think that it can be safely assumed that it was CLEAN!:rofl:

I'm also taking you at your word that you had the boat cleaned by divers every month or so for the 12 months prior to hauling out and installing the sonic anti-fouling system. :thumb:

To all: Let's try and support the effort Wdeertz is going through in order to provide some basis for evaluating his install instead of twisting his words to insinuate he is unjustifiably libeling his diver, shall we?:D

Bruce: Thank you for pointing out the "Be Nice" rule in the Forum Rules. It is a rule that we do indeed take seriously. Thank you all for understanding!:thumb: Now let's get back to boating, shall we?!?:dance:
 
I'm looking forward to seeing your documentation on the efficacy of the system you installed! It will be nice to see factual, pictorial data.

In the absence of photographic evidence of what the bottom looked like after cleaning and applying three coats of bottom paint, I think that it can be safely assumed that it was CLEAN!:rofl:

I'm also taking you at your word that you had the boat cleaned by divers every month or so for the 12 months prior to hauling out and installing the sonic anti-fouling system. :thumb:

Here's the rub: Ultrasonic Hull systems have been around for quite a while but the evidence of efficacy is mixed (at best). Worse, it is entirely anectdotal so there's no telling why it works in some cases and not in others. Heck, it's entirely possible it rarely works but rather the owner 'wishes' it into the success column.

From last year, here's a BoatTest video that, on the surface, is compelling. Gives plenty of photos showing a successful install. I reached out to Hull Shield after seeing this video last year and asked some questions to see if they had more behind the curtain than owner testimonials. I was pretty direct - for me, a 'twin study' on a catamaran with one hull protected and the other without would be tremendously helpful. I even volunteered my friends 52-foot Power Cat. The response was that they were working with Aquilla to be factory installed optional equipment.

My takeaway is Ultrasonic Hull contraptions might work in some situations, but there's no telling what those situations are. I assume they sell 100's of these things yet I rarely read anyone who has one or has first hand knowledge of someone who does. So I have to wonder. The Hull Shield rep I talked to pointed to incorrect install as the reason for all duds - has to be kept energized 24/7. And has to be installed with fresh bottom paint. The device will not reverse growth, only abate it.

Like most owners, I'd gladly fork-over the $1500-$2000 if the system only did half of what they said it does. I tried to get more empirical and quantitative information, but it just wasn't there. At least for my tastes.

Peter

https://youtu.be/MRDVtVMKp3c?feature=shared
 
No these were monthly cleanings over a 3 month period. I took the boat out a week after the supposed last cleaning. No way an inch of growth in only a week. The funny thing is if the growth was so bad that the diver needed more time I would have gladly paid additional. Nope just kept collecting his fee and never said anything.

I have a friend who just had a similar experience in Charlotte Harbor. He has a diver clean his hull monthly. 2 weeks ago I rode along as he went for a haul out. Once in the slings we found the hull in good shape but the running gear was completely covered in hard growth. We didn't notice while we were running as we were going slow to time the haul out appointment.

He asked the yard manager what he thought and the answer shocked me..."In Florida divers just clean the bottom unless you specifically request the running gear cleaned. Then it's extra". I had no idea this was SOP for divers around here. The diver never mentioned this to my friend, just cleaned the bottom and moved on. You may want to ask your diver if that's his practice too.
 
He asked the yard manager what he thought and the answer shocked me..."In Florida divers just clean the bottom unless you specifically request the running gear cleaned. Then it's extra". I had no idea this was SOP for divers around here.

It's not, I guarantee it. Just another boatyard employee who doesn't know what he's talking about.
 
It's not, I guarantee it. Just another boatyard employee who doesn't know what he's talking about.

I agree - that's a ridiculous statement by the yard (that divers don't do running gear).

In Mexico, very common for workers to send pictures of work completed. I've had my bottom cleaned a few times while in Mexico - they provide pictures of everything including condition of zincs, etc.

Sounds like you need a new diver. And perhaps a Yard. That was crazy.

Peter
 
Not sure how a diver on the west coast can guarantee standard practice in Florida but OK. Seems that a yard manager in a reputable boat yard would have a clue. Do you have a professional opinion on how that much growth attached to the running gear in the 2 weeks since the last cleaning?

It's not my boat or my diver, I was just trying to help the OP find a possible solution. I'll butt out now....

Sorry, not the OP but Wdertz.
 
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Hello,

I installed an ultrasonic system on our boat 2 years back.
The system consisted of two transducers and a control box.
In addition to the power consumption, which is considerable because it is continuously on, the noise produced by the transducers can also be a nuisance.
But the conclusion, with us the system did not work at all!
After two months, the boat had grown to such an extent that the speed decreased by 2 miles.
Eventually, old-fashioned antifouling was applied again.

Mvg,

Pascal.
 
Not sure how a diver on the west coast can guarantee standard practice in Florida but OK.

I admin a Facebook group for professional hull cleaners. Hundreds of Florida divers are in it, many of whom I know personally, some of whom I have met and others with whom I have had phone conversations. I am quite familiar with how they run their businesses and when I say that ignoring the running gear is not SOP for them, you can take that to the bank.

Seems that a yard manager in a reputable boat yard would have a clue.

Boatyard personnel rarely see a particular boat's bottom more frequently than every couple or three years. They sure as hell have never cleaned one on a regular basis as a diver and therefore have no idea what is, or is not typical practice for a hull cleaning business. I have been doing this for almost 30 years and I only wish I had a dollar for every piece of ignorant BS about in-water hull cleaning, anti fouling paints, divers etc. that I've heard come out of a boatyard employee's mouth. Boatyard owners too, for that matter.

Do you have a professional opinion on how that much growth attached to the running gear in the 2 weeks since the last cleaning?

I don't have any idea how much growth you are referring to. You didn't provide any pix or even a detailed description of it. That said, it is certainly possible that your friend's diver did not do a proper job, whether intentionally or through carelessness. But it is also possible that the two of you have unrealistic expectations about the amount of fouling that is possible in a short time on (what I assume is) unpainted underwater metals during the summer in Florida. As someone who earns his living doing this, I have experienced that potentiality from both boat owners and yard employees more times than I can remember. Especially now that climate change is a reality and is absolutely affecting fouling rates in both California and Florida.
 
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I installed an ultrasonic system on our boat 2 years back. But the conclusion, with us the system did not work at all! Eventually, old-fashioned antifouling was applied again.

Even the manufacturers (well, some of them anyway) will admit that these systems are not a replacement for anti fouling paint but rather designed to work in conjunction with anti fouling paint. Although my personal experience (like yours) is that they do not work at all.
 
Ultrasound antifouling

I looked into it and just couldn't justify the cost. You still have to haul and paint the bottom at your Regular intervals. So I figured I might save a few diver costs a year but no way near the cost and installation of the antifouling.
 
I had a boat in the water for 40 plus years and have gone through many divers ( some good and some not so good) all cleaned the running gear without having to ask. It’s part of the job. If you find a good bottom guy treat him like a god because he is worth his weight in gold ( unfortunately many don’t last). I bought a house on the Miami River that is brackish which helps.

My wild ass guess is this product is a transfer device. It’s job is to transfer your money to theirs. :)
 
When I was the engineering department head for the USCG small boats in New Jersey, the USCG did extensive research to find the most environmentally friendly antifouling system available.

Not sure what they ultimately chose and that it was widely used for all USCG vessels from Icebreakers to small boats as I was assigned different duties in the next year or so.

Bottom line is the USCG, US Navy and probably every major shipping company has done research on this topic, might be advisable to look there for research probably done with fairly strict parameters if you are very interested in any particular system.
 
Would think (but don’t know) ultrasonic systems would be more effective on metal hulls. Would think (again don’t know) that intensity of of transmitted vibration would dissipate less for a longer distance. Oiled think this tech would be less effective with cored hulls and might even produce damage over time. From the little I do know energy involved is quite low so probably not a concern for solid grp.
Some here are quite knowledgeable about ships. Of course they are usually metal. Do you folks have any insight on applications in metal hulls?
If I recall correctly Fast isn’t a fan of ablative. Seem to recall him posting on Sailnet to that effect. Personally like ablative on slow boats like FD trawlers and non racing sail. Mention this because I wonder if this tech causes bottom paint to leach faster. Especially germane at times you’re not moving. Thoughts?
Do know that places that aren’t structurally part of the hull are problematic for this tech and if possible additional pucks for them are required or foul unimpeded. So wonder as to utility as you would still need to dive and /or haul if areas can’t be covered effectively .
 
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Do you folks have any insight on applications in metal hulls?

My understanding that ultrasonic systems are sometimes used on large commercial vessels to keep seachests etc. free of shelled animal fouling. Not effective on large areas of the hull, however.

If I recall correctly Fast isn’t a fan of ablative. Seem to recall him posting on Sailnet to that effect.

You recall incorrectly.
 
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