For correction, my 35 years in north european waters was that we do have major problems with fouling both weed and barnacles
. Antifouling that worked well one year would not work the next with the bottom looking like a shellfish farm. That was in the south UK. We are now in the Med Adriatic
and again there are problems requiring a mid season scrape.
There have been tests from reliable sailing mags like Yachting Monthly which indicates that ultrasonic can work. At this years boat show
, I talked to a supplier who claims to have a large order from USCG, after successful trials, perhaps some of the US contributors with contacts there could check that out. I understand they are using it to protect sea inlets etc. I have a similar concern to protect my saildrives and keep the water inlets clear and reduce fouling in that area.
Like everything on the commercial
marketplace, some stuff ostensibly using the same technology will work better than others either because of the implementation or installation
. Thats what this forum is for, we just need people to share real experience.