Sonihull Testimonials

Anderson Island Fire/Rescue operates a 2014 Armstrong Marine, aluminum fireboat weighing in at 16K pounds. It is 34 feet in length with 32 feet at the waterline. It is a Catamaran design with two, 300 horsepower, Mercury Verado V8's. When the hulls are free of growth and barnacles, it usually runs at a top speed of around 41 MPH, but the unprotected accumulation of algae growth and barnacles would cause it to slow down to about 33 MPH over a period of 6 months of haul out and hull cleaning. This condition used more and more fuel for each emergency patient run and increased the time to reach advanced medical aid. Haul out had to be accomplished every six months. After hearing about the Sonihull product from PYI Inc, and with tons of internet research, it was decided to put a Dual Sonihull system to the test on the boat. Skepticism ran high among the veteran boaters as to the effectiveness of the Sonihull. My team thoroughly cleaned the hull of barnacles by scraping and power washing and we applied three coats of bottom paint. Then the Sonihull was installed utilizing the supplied instruction and a few phone calls with Phil at PYI Inc. It took two days to finish installation. The epoxy drying overnight was the only reason it took two days. One transducer was installed for each cat hull. The AC shore power is always plugged in while moored and the DC power operates the unit when shore power is not available. The Sonihull runs continuously 24/7. It has been three years in July since the bottom has seen a barnacle or significant growth. Now the only reason we have to pull the boat out is for annual motor maintenance on the outboards. Sonihull has paid for itself in the costs of approximately five haul outs to pressure wash, two bottom repaints, and the decrease in fuel cost due to the drag the previous barnacles caused.

- Jeff Hayes, Captain, Marine Division, Pierce County Fire District #27, Anderson Island WA.

I want to thank you for your advice to install aboard my ship two SoniHull DUO... I am, after one year, really very happy with those devices. My ship, a 65 Ft steel trawler, has stayed one full year in Brunswick Landing Marina. Here everyone sends a diver every two months for cleaning his hull off the growth, so I have asked the diver to check my hull, after one year without cleaning... The guy was realy amazed by the fact that my hull was still perfectly clean... Except for some barnacles on the shafts and propellers, so my only regret is not to have installed the sonic system for the shafts as well. This system is realy great and super efficient. Thanks again for this product.

- Pierre

I did the install myself in our 2014 Leopard 48 in February 2020, and I installed the two transducers ahead and behind each keel where I’d confirmed with Leopard that the glass is solid - coring starts at least 10” up the side from the centerline. I located the two controller boxes on the side wall inside the two hulls’ A/C compartments, which provided a central location to reach the transducer mount points. The boxes are watertight and could go in the bilge, but I wanted them up where I could easily see them.

The controllers have both 110v and 12V power connections, and to confirm no distinction between them, I ran one on 110v and the other on 12V for a year full time. It pulls the equivalent of 12v 0.6A for each controller. I power-sanded the mount sites to ensure each was completely flat, stayed clear of the bulkheads and followed the instructions meticulously to make sure the transducer-to-hull contact was complete (they have you cover the face of the transducer with Vaseline to ensure complete contact).

Barnacle Control:
At the time of the install, I had cleared the bottom of all of the 1/4-1/3” barnacles, leaving the little round white disks that remain after the main of them is removed. Our bottom paint is Sea Hawk AF-33 and it was last bottom painted In February 2019.

We have been in the water in the Keys and at Port of the Islands south of Naples for over a year since, and while I don’t dive in the marina or anchored out in the 10,000 Islands (alligators and bull sharks), I did finally dive her when we visited Islamorada after Christmas after 10+ months in the water without any bottom cleaning of any sort.

Bottom Line:
The SoniHull appears to work. I could count the active barnacles on two hands across both hulls, and they came off easily with a plastic putty scraper. There were only the inert discs from where I’d scraped the pre-SoniHull ones off. For comparison, our new kayaks were covered with pre-barnacle “worms” after only a few weeks in the water. There was no distinction between the hull using a 12v powered controller and the one using 110V. Even the keel was relatively barnacle free:

Keel barnacle free with Sonihull

Here, you can see the remnant barnacle “discs” from the pre-SoniHull barnacles are there, but almost none were active barnacles.

Barnacle discs from pre-Sonihull

Side Note:
Imagine my surprise when, after confirming the port hull was barnacle-free, I swam over to the starboard hull and found that the prop nut (improperly installed by MultiTech using the wrong bolt size) had fallen off some time since last summer, yet the prop miraculously stayed in place!

Propeller with no fouling due to Sonihull

MultiTech’s post-sail drive service photo reveals they used a makeshift non-OEM bolt, that is too long, deflected, and likely not the right diameter to be threaded in securely:

propeller on saildrive

I had to order an OEM nut kit to be delivered general delivery to Islamorada before New Years, then installed it in the water. The good news is that the sail drive and props appeared to have been protected by the SoniHull effect as well. After I replaced it the prop bolt is correctly sized, not over length:

Saildrive propeller with Sonihull

Noise Level In Operation:
When I swim below the hull with the system active, the audible chirp it makes is very sharp and even uncomfortable - I usually try not to have it on when I am down there close to the hull. Apparently the growth organisms are similarly deterred.

Inside the boat and with everything mechanical off, the chirp is barely perceptible except that I know its pattern of three bursts “click click click” and can hear the faint clicks only in the bright-walled master bathroom when there are no waves and wind. If anything is on (fan) or waves are lapping the boat, you will hear nothing

That’s my experience - your mileage may vary, but I am very glad to have gotten the SoniHull.

- Jim S., Leopard 48, Naples, FL