Galvanic Corrosion and Stray Current Corrosion are complicated topics. The goal is not to discuss them technically here, except to focus on warning signs, and how it impacts your anti-foul and/or foul release.
If you really want to go down the rabbit hole start with Nigel Calder's excellent videos (Google "Nigel Calder current corrosion"), other examples like Boat-us-expert-advice-marine-corrosion-101.
Current corrosion can be a silent saboteur, wreaking havoc on your vessel’s underwater metals if left unchecked, and very quickly too in some circumstances.
The good news? Velox Plus can alert you to the problem, giving you good notice to protect your boat effectively. Let’s dive into the signs, consequences, and most importantly, the fix for this common maritime headache.
Tell-Tale Signs
Electrical discharge leaves behind distinct clues, and catching these early can save you from costly repairs. Here are some key indicators to watch out for:
- Fast-growing or oversized barnacles, on metals coated with cuprous oxide-based hull anti-foul.
Hull anti-foul paints, when applied to metal surfaces with electrical charges running through them, can inadvertently fuel barnacle growth. This happens because the charge produces gases that energize &/or force-feed them. Meanwhile, non-metal surfaces (i.e. the hull) remain relatively clean, creating a stark contrast. You may also see baby barnacles on surfaces (e.g trim tabs) down-steam from the main barnacles hatcheries. - Blasted-off coatings
Silicon foul-release or Velox Plus coatings can be stripped from metal surfaces due to the discharge. You might not notice this as much with PropSpeed due to its colour similarity to the metal, but the issue persists. - Brightened, exposed metal
If the exposed metal is shiny and with little evidence of oxidization, electrical discharge is the culprit.
The Good News
Not all is doom and gloom! The right tools and techniques can help mitigate electrical discharge issues while preserving the integrity of your vessel.
- Velox Plus works hard for you
Velox Plus remains effective, thanks to its surrounding biocide layer. - Scrubbing is a breeze
Any barnacles that do form can be easily scrubbed off without specialized equipment. The durable nature of Velox Plus ensures it doesn’t wear down easily, even after a good cleaning.
These benefits are great but they are only buying you time. You need a strategic FIX.
The Fix
If your vessel is suffering from electrical corrosion, there’s no time to waste. Here’s a step-by-step plan to get things back on track:
- Consult a marine electrician
An expert can identify and remediate the source of the discharge. Whether it’s faulty wiring, an improperly bonded system, or a stray current, a professional diagnosis is essential. - Remove hull anti-foul from underwater metals
Anti-fouling paints with cuprous oxide aren’t suitable for metal surfaces exposed to electrical currents. These paints can exacerbate the problem, so it’s best to strip them off entirely. - Coat all underwater metals with Velox Plus
Consistency is key. Make sure every piece of underwater metal is covered with Velox Plus to create a uniform layer of protection. - Prime with Marlin Paint’s Metal Primer
Thanks to an important research and development project carried out in collaboration with universities and research laboratories, Martin Paints Metal Primer has been recently improved with innovative adhesion promoters and galvanic current inhibitors.
By following these steps, you can protect your vessel from the harmful effects of electrical discharge and keep it in peak condition for years to come.
Electrical discharge is more than just a nuisance - it’s a serious challenge that demands attention. But with the right approach and the trusted protection of Velox Plus, you can keep your vessel safe, efficient, and ready to sail smoothly.
Disclaimer: Not a Silver Bullet
The Velox Plus system is excellent - but it’s not magic. Enough voltage or force can damage surfaces, equipment, or surroundings. Follow the guidelines. Use the right settings. Browse our valuable resources below.

Coverage Chart
Guide only. Remember that even once opened you can lid these products for years, so if in doubt there’s no downside in over-estimating. click here for PDF

Apllication Guide
Including Assessment, Preparation, Coverage, Recommendations, Tips & Tricks click here for PDF
Stray Current and Galvanic Corrosion & Underwater Metals