Sailing Zephyr IVvideo
Ultrasonic Anti-Fouling Test: Will the Seaflo System Deliver?
28 June 2026 · 10 min · 26K views
Sailboat High Spirits lifted by crane at marina
What this video covers
Dave installs a Seaflo ultrasonic anti-fouling system on a Jeanneau Sun Odyssey 35 named High Spirits, owned by Derek, after a Chinese manufacturer sent a free unit for evaluation.▶ 1:54 The system includes a control unit with screw-in waterproof connectors, four epoxy-bonded transducers, four cables, and extension cables.▶ 0:44 Derek positions three transducers along the hull's wetted area and mounts the fourth directly on the gearbox to protect the propeller shaft.▶ 3:11 Installation required cutting one cable plug to route wiring through the boat's tight interior, then soldering it back on.▶ 5:17 Power draw measured approximately 1.4 amps continuous — higher than expected — drawing from a 300 amp-hour battery bank kept charged at the berth.▶ 6:09 Derek rates build quality as high: solid transducers, waterproof O-ring cable connections, and a five-amp internal fuse.▶ 4:27 The boat had already been in the water 12 months when the system was fitted, so Seaflo's requirement to run from first launch was not met for this cycle.▶ 7:45 At haul-out in late April 2026, the hull showed no hanging weed and no barnacles, but carried a thick slime layer that wiped off easily.▶ 9:17 Derek considers the bottom slightly cleaner than usual.▶ 9:33 The definitive test will follow the next full season with the system running from launch day.▶ 10:02
Boats in this video
More from Sailing Zephyr IV
From Sailing Zephyr IV — see the channel’s boat, crew, and every analysed video.
The Sailing Directory Newsletter
One email with the fleet's best finds — the moments, boats, and stories worth your watch time. Enter your own address to get your own copy.