Marine Corrosion Prevention. Permanently.

 In a hurry? Fast response, minimum of your time:  email Glen Bishop.
Free Technical Support online or phone by Marine Electronics Engineer with two degrees and 50 years defeating corrosion. Glen Bishop.

SeaBis Master System guarantee (physical properties), warranty (functional properties) and diagnostic support, are free for minimum 8 years. No skill required. We will provide the skill and step you through preventing the CAUSE.

There are persons who will benefit from NOT preventing corrosion. Ask for their Guarantee AND Warranty. IN WRITING or view it YOURSELF.

Information in this website will save you at least $10,000 so press Ctrl+D to save 

We prevent the CAUSE of marine corrosion, stray current, permanently. The movie, next, is an extremely complex yacht with 3 battery banks, sonar, radar, radio, computer systems and others.  The Owners live on board with permanent commercial use.  Most vessels only need one SeaBis Master.

 This tall yacht is an old tanker hull. Old hulls and engines need not cause corrosion.

Marine corrosion, stray current, prevention, permanently.

corrosion protection stray current prevented from causing marine electrolysis corrosion, permanently



Electrical stray current dissolves your metal by electrolysis. SeaBis System prevents ALL stray current. Paint bubbling, metal dissolving is solely caused by stray current. So SeaBis System stops paint bubbling, boat or marina corrosion, rust, rig and process line corrosion. The SeaBis System prevents them all.




Corrosion is dependent on an electrical – chemical reaction. Prevent the corrosive current and you will prevent 97% of all marine corrosion from occurring. On your boat, yacht, plane, vehicle, caravan, train. Wherever there is a battery or DC (solar, wind, diesel – anything that generates DC power)  and metal.




SeaBis Master System indicates the DC power side (positive or negative) so halving your work. It indicates the severity so you know the degree of urgency. The User (anyone) switches off equipment until SeaBis indicates Normal (green). The last equipment you switched off was the cause. Now follow How To Stop Corrosion or contact us.


In excess of 2,000 vessels cleared of CAUSE of corrosion – stray current.

Stray current protection is provided by SeaBis System, permanently.

No skill required.  We will train and step you through CAUSE prevention, permanently.

Therefore, we provide 8 years Diagnostic support, Warranty AND Guarantee.

Absolutely not. Reason is AC is short for Alternating Current. It reverses direction every half Cycle or Hertz.  So, IF it takes off a particle in first half Hertz it will replace it in second half Hertz. So AC cannot cause marine corrosion.

Some will say that AC may contain DC (Direct or battery Current).  IF that were so there would be no Back EMF or Counter Motive Force.  So, nothing to control the flow of current.  Resulting in EVERY  AC appliance burning out.

So why buy a Blocker? Wikipedia Back EMF or Counter Motive Force

Marine corrosion protection commences with understanding: DC is short for Direct Current. It flows in the same direction permanently. So, it will permanently remove particles of your metal to the Earth (the Earth we stand on), termed marine electrolysis. Sometimes termed stray current. DC is the only cause for marine corrosion: Wikipedia explains. So procedure: prevent the marine corrosion with SeaBis Master System.

Marine corrosion is caused by stray current, not voltage.  Therefore, only SeaBis will assist.  Others will in fact create confusion. They all measure the voltage of every vessel within 150 meters when the cause is current.  Others can only deceive you while corrosion is ongoing.

A one kilogram (2.2 pound) anode produces 0.000001 amp of protective current. Marine corrosion or stray current starts at 0.0001 amp and is commonly 1 amp. I have measured nearly 10 amps. Therefore, you would need at least 1,000 Kilograms anode to make any reduction in marine electrolysis. Much more practical and cheaper to eliminate stray current that is the CAUSE.

Different metals such as stainless and aluminum, when very close together generate a very low value current. It is in the millionths of an amp. That results in galvanic corrosion. It takes many months for that corrosion to be visible. However, it is accelerated by stray current. Therefore the procedure is to prevent marine corrosion then prevent galvanic corrosion by adding non-metal between the two or anode.

Yes, because the same stray current flows. That stray current is unlikely to cause severe marine corrosion as the only current path to the Earth is via the air. Dry air is an insulator. Damp air is conductor so will cause corrosion.

You can prevent all causes of marine electrolysis with one SeaBis Master. However, if you have more than one battery bank that is not switched in parallel you have choices:
Move SeaBis every 10 days battery bank to battery bank or fit a parallel (both) or (emergency) switch or fit one SeaBis per battery bank. Above all one SeaBis per battery bank provides 100% early warning of stray current corrosion.

Advice is free: Glen Bishop email: [email protected]

An industrial marine grade micro computer with a design life of 20 years. We guarantee (the hardware) for 8 years.  We warranty (the function) for 8 years.  Manufacturers’ faults only. We offer free diagnostic and repair online support for your vessel for 8 years. Support by a Marine Engineer with two degrees and a life time defeating corrosion. See About.