Corrosion Knowledge Base

This Corrosion CAUSE Knowledge Base will be used by SeaBis to prevent corrosion.  Not essential for you to read.

Language translater page bottom

Language translator at the button on page bottom – left.

Marine corrosion prevention, permanently
How to Prevent Marine Corrosion. 8-year guarantee.

Corrosion Knowledge Base. Stop CAUSE.

This corrosion knowledge base is not essential to you.  We will guide you or step you through stopping the only cause – stray current.

Now, one critical hard fact: Please consider vehicles:

Corrosion in vehicles is mostly stopped.  Because they are on rubber tires.  Therefore, there is no electrical contact to the Earth.  SeaBis Master System has the same effect. The result will be no current flowing to the Earth and those boats around you. SeaBis LED’s will be Normal (green). Permanently. No extra coating, plating, moving parts or through wall. We prevent ALL  CAUSES.

Avoid a 1% risk of loss of your vessel.  Use the SeaBis Master System. Stop CAUSE using corrosion knowledge base.


Table of Contents

Stop CAUSE. Use the corrosion knowledge base.

Proof that we are genuine: click here.

Additional: no electrical knowledge required. 

Even if you do not know what a fuse is. As part of your purchase of SeaBis Master.  We will step you through How to Prevent Marine Corrosion – free.

SeaBis Master System prevents the CAUSE of electrolysis corrosion.
Marine corrosion CAUSE prevented, permanently

Corrosion Knowledge Base.

SeaBis Master LED’s explanation:

SeaBis Master halves your work by indicating battery negative or positive.

SeaBis Master sensitivity is 10 millionths of an amp.  Corrosion starts at 20 millionths of an amp.  Multimeters, apart from being in the wrong circuit and risking your life, have an accuracy of 200 millionths of an amp.  They worsen the situation.

1: Normal (green) = there is no corrosive current.

2: Caution (amber) = very low current.  There is a risk that faults may become serious

3: Serious (red) = visible corrosion in 6 months

4: Critical (flashing red) = visible corrosion within 3 months. I regularly experience 10 days.

5: AC Only (flashing red) = your batteries, electronics and yourself are at risk. AC (110/240) on top of DC (battery) exceeds 2 volts.  It is normally 0.02 volts. 

AC Only flashing red may be a warning of lethal risk:

*** A common cause is Mains or Shore power Active, Neutral or Earth reversed. So, your life is at risk. *** 

If in any difficulty please contact me, Glen Bishop

How to prevent marine corrosion. Understand the basics.  Use the corrosion knowledge base.

1: Stray DC (battery) electrical current is the actual energy that dissolves your metal. SeaBis Master measures and indicates DC current as DC current. To the accuracy of 10 parts in a millionth of an amp.

2: Voltage is not energy. It is POTENTIAL, subject to many other factors, to vary the current. Voltage can be measured cheaply. However, without knowing ALL the other factors, and that is impossible, measuring voltage is valueless. Corrosion will be escalated.  Current energy is the energy that causes all corrosion. We term that the current Stray Current.  The SeaBis Master System prevents Stray Current 100%.

3: Mains, inverter or shore power is termed alternating current (AC).  It reverses the current direction every 1/100 or 1/120 seconds.  IF it took off a particle in the first 1/100 seconds, when it reverses in 2/100 seconds it would put it back on. Therefore, mains, shores or inverter power (AC) cannot be the cause. Devices installed in the shore power connection are trying to prevent battery (DC) in the AC.  It does not exist. So, how good are they? If there is any corrosive current in the AC, then SeaBis will flash red. SeaBis with How to Prevent Marine Corrosion will isolate shore as CAUSE. I have cleared more than 2,000 vessels of corrosive current. I have never known AC to be a cause. 

4: “I never had corrosion this bad before”. Explanation: as the metal surface roughens, so its area increases. As the area increases, stray current increases …

5: Stray current is directly affected, linearly, by the speed of water past the metal. Therefore, propellers attract and conduct stray currents far worse than most static metals.

Contact us as part of your purchase of SeaBis Master System.  We will step you or others through corrosion CAUSE prevention.  100% effective. Permanently. 


Diagram explanation of why SeaBis System is 100% Successful. Use the corrosion knowledge base.


Corrosion knowledge base.  How to Prevent Marine Corrosion, understand the CAUSE:

Voltage versus current – critical importance. 

Voltage is the POTENTIAL for current to flow.

Current is the ACTUAL energy flowing.

Therefore, measuring voltage, always by a multimeter, probe etcetera MUST fail.  That failure WILL cost you increased corrosion in an *exponential manner.  Using SeaBis Master so measuring CURRENT with absolute accuracy then disconnecting until that current ceases WILL prevent the CAUSE.


Exponential corrosion.  Use the corrosion knowledge base. 

I often hear, “I had no corrosion until a few weeks ago.”
Explanation: As the metal becomes rougher, its surface area increases. That increases the (stray) current flow. Therefore, increasing corrosion, exponentially. In conclusion, I have witnessed a 10-day time period from no to extreme corrosion too many times. Therefore, use SeaBis Master with How to Prevent Marine Corrosion, now and permanently.

Stray current – ONLY CAUSE:

It is powered by direct current (DC, as in batteries). Stray current dissolves your hull, propeller, gearbox, engine and upper deck fittings and fixtures by electrolysis via damp air or water.  Additionally, the metal beneath the coatings and plating dissolves, causing them to lift off the metal. In conclusion, SeaBis Master System prevents the CAUSE of stray current.  Permanently. In addition, the SeaBis Master System works 100%.  No additional anodes, coating, plating, through holes or moving parts. Then the anodes, coatings and plating can work as designed.

Corrosion knowledge base.  SeaBis Master System accuracy:

SeaBis Master measures and displays the current as current.  With an accuracy of ten parts in one millionth amp. The SeaBis Master System identifies CAUSE.  SeaBis Master, with How to Prevent Marine Corrosion, repair the CAUSE.

Technical explanation (easily understood). Use the corrosion knowledge base.


Stray current creates electrolysis corrosion. Stray current is ONLY caused by DC.  SeaBis Master System, with How to Prevent Marine Corrosion, permanently eliminates the CAUSE – permanently. 

Rust, electrolytic action, marina corrosion, boat corrosion and galvanic are all common terms used to describe the effect of stray current. All are CAUSED and / or vastly accelerated by the stray current that causes corrosion.  All can be prevented, permanently.

Rust is simply air carried current.  Often vastly accelerated by stray current. 

Stray Current or Galvanic Corrosion?

Stray current dissolves your metal.  It is ONLY caused by DC (battery power).  It cannot be caused by AC (mains or shore or inverter power).  Full stop. Permanently.  In 20+ successful years of 100% stray current prevention, I have never experienced AC cause DC. Proof at (link:) Wikipedia-electrolysis.  Note the power supply and text description clearly state DC (battery power). Not AC (shore power).

Galvanic corrosion explanation:

Galvanic corrosion is ONLY caused by two different metals nearly touching in a conductor.  Such damp air or water.  In conclusion, the only examples I know of are a stainless-steel ladder touching an aluminium hull. Or an aluminium cupboard with stainless steel knobs.  Both without insulation. Insulation or anodes will prevent galvanic corrosion.
Galvanic is a million times slower than stray current corrosion and is nearly always caused and accelerated by stray current.
Stop the stray current, and you stop at least 97% of corrosion.  Anodes, when stray current corrosion is eliminated, will stop galvanic corrosion and should last 3 to 4 years.  However, if they do not last 3 to 4 years, or are coated in a jelly or white hard substance or are dissolved far too fast or not at all, then stray current is the ONLY cause.

Corrosion knowledge base. Stray current is the ONLY cause of all this corrosion:

All the following were ONLY caused by stray currents generating electrolysis corrosion.  None caused by galvanic corrosion (different metals nearly touching).  Above all, all WILL be prevented by SeaBis Master with How to Prevent Marine Corrosion, permanently.  In conclusion, galvanic corrosion is easy to prevent when stray current is prevented FIRST.  We will advise you.

How to prevent marine corrosion: Use the corrosion knowledge base. 


The ONLY cause is stray current, via air or water.  Stray current corrosion is caused by wiring or equipment defects onboard your vessel – 99% of the time.  I witness stray current destroy propellers or hull or engine or upper deck fixtures and fittings in 10 days, many times every year.  It is DC (battery) current flowing from your vessel to the Earth. Taking your metal with it to the Earth.  This is where SeaBis with How to Prevent Marine Corrosion, permanently, pays for itself, very quickly.  SeaBis System prevents the CAUSE – stray current.  Therefore, saving you many thousands of dollars.

The stray current through electrolytic action, termed electrolysis, generates marine corrosion. So, the original marine corrosion cause is your vessel (battery) creating stray current.  If you need additional clarification, contact us.

After SeaBis Master System:

One year submerged:
After SeaBis. Antifouling works as designed.
After SeaBis. Utopiall a year submerged. Marine electrolysis corrosion prevention identifies then prevents the stray current that is the only CAUSE. Permanently. Antifouling works as designed.
After SeaBis. No stray currents. Antifouling works as designed.
After SeaBis. Utopiall underwater view. A year submerged. Marine electrolysis corrosion prevention stops ALL stray current. Antifouling works as designed.

Our guarantee, warranty and support:

The reason we provide an 8-year guarantee (the equipment) and warranty (the function) with SeaBis Master is, we are 100% correct.  We supply 8 years diagnostic support as causes will reappear with new equipment, water ingress, insulation failure or carbon build up.

Testimonials at:

Do not waste your money:

Corrosion knowledge base.


Anodes? Can I add more to prevent corrosion?

A one kilo gram (1,000 grams) or two pound anode generates 1/(divided by)1,000,000 or one millionth of an amp protective current. In comparison, stray current is 100 to at least 1,000,000 times stronger. Therefore, you would need 100 too at least 10,000 kilo grams of anode!  It is far cheaper and is practical to use SeaBis Master System with How to Prevent Marine Corrosion to prevent the CAUSE, completely and permanently. 

Multi meter, half-cell, reference electrode or test lamp? 

Can any of them prevent corrosion?

Sorry but no. The consequence will be to waste your time and money while corrosion escalates. The reason is, corrosion is caused by DC   CURRENT flow to the Earth. All the above measure the COMBINED VOLTAGE of every vessel within 200 meters and that of the Earth. They do not measure current. The result is misleading information.  Therefore, use SeaBis Master with How to Prevent Marine Corrosion to measure current flow to the Earth.  Then correct the cause – SeaBis Master System works 100%. In conclusion, that is why we provide an 8-year guarantee and warranty. 

Why waste your money while corrosion escalates?

How to Prevent Marine Corrosion versus Blocker or Transformer?

Some will try to confuse you by calling Blocker or Transformer a Galvanic Isolator! Galvanic corrosion is ONLY caused by nearly touching different metals.  This includes, a stainless-steel ladder against an aluminium hull or aluminium cupboard with stainless-steel handle, both without insulation. Treating the public with such contempt can only cause contempt.

AC and shore power:

AC cannot be the cause, so what does the Blocker or transformer achieve? Explanation:

If there is any corrosive current in the AC, then SeaBis will flash red. SeaBis with How to Prevent Marine Corrosion will isolate shore as CAUSE.  With more than 2,000 vessels cleared of corrosive current, I have never known the main / shore power to be a cause.

Don’t be deceived. AC – Mains / shore power CAN NOT be the cause. Above all, the reason AC is the abbreviation for alternating current.  It reverses the current direction every one hundredth of a second.  Therefore, IF it removed metal in the first one hundredth second, it would replace it in the next one hundred of a second. Therefore, AC cannot be the cause.  In addition,  if it were, then SeaBis would flash red.  SeaBis System would identify AC as the cause.

Corrosion knowledge base.  VERIFY their claims.

Ask for their WRITTEN guarantee and store it.  You will need it.

SeaBis WRITTEN 8-year Guarantee (the equipment) and Warranty (the SeaBis System), click: SeaBis guarantee and warranty,

Some will claim there is DC (battery power) in AC (shore power).  If so, then every AC appliance would burn out in a few seconds. Reason: DC creates no Counter Motive Force (Back EMF). Verify: Wikipedia – Counter Motive Force, Back EMF: 

Shore connection:

It is extremely unlikely the shore connection is the cause. The SeaBis System with How to Prevent Marine Corrosion will correctly indicate, then repair, the causeIF the shore connection causes DC in the AC, then SeaBis Master will flash red.

Reduce your work by 50% with How to Prevent Marine Corrosion:

Your work is reduced by half: For instance: SeaBis Master indicates the battery side, positive or negative, that is causing the corrosion.

Life expectancy for SeaBis Master:

SeaBis Master with How to Prevent Marine Corrosion is an industrial grade mini-computer system.  SeaBis has 20 years of design life.  Compare costs – try buying an industrial grade minicomputer with 20 years of design life.

It is the simplest and most direct way to eliminate the CAUSE of marine corrosion.

Blocker or transformer is not required:

You do not need a Blocker or transformer when you use SeaBis Master with How to Prevent Marine Corrosion. The reason: SeaBis Master will flash red in the extremely unlikely instance where shore power causes corrosion. 

Portable SeaBis:  How to Prevent Marine Corrosion.

SeaBis Master with How to Prevent Marine Corrosion can be fitted with battery clips to make it portable.  There are limitations:

SeaBis Master may be moved to more than one battery bank, and How to Prevent Marine Corrosion will prevent all permanent CAUSE/S of stray current. To identify Intermittent stray current (moisture, carbon, equipment or wiring failure) requires SeaBis to be permanently installed. So if you use one SeaBis Master fitted with battery clips to move SeaBis to more than one battery bank, then every battery bank must be interrogated by SeaBis Master at a maximum interval of 7 days. Then How to Prevent Marine Corrosion will prevent the CAUSE.   Therefore, no electrolysis corrosion can occur and galvanic corrosion is easy to prevent with insulation or anodes. 

Corrosion knowledge base.  Commercial use vessels:

Using How to Prevent Marine Corrosion.

Procedure to repair CAUSE of stray current where engine ON hours exceed 200 per year.

Using SeaBis Master System with How to Prevent Marine Corrosion, identify sensors that cause something other than Normal.  Replacement of correctly insulated Sensors available at: A.S.A.P. Supplies in the U.K.  The manufacturers are Teddington. Senders and switches that are all correctly insulated.

To get the thread exactly correct, use a thread gauge from a Fastener Retailer.

Using SeaBis Master System with How to Prevent Marine Corrosion.  Identify starter motors, alternators or sensor terminal insulation that are caused other than Normal.  The cause is often carbon build-up around brush holders or bad design. Commonly corrected by automotive starter motor and alternator re-winder. Obtain wires and crimps to replace the connections that used to be made by the engine body with wired connections.

In conclusion, if you have any difficulty, we will talk you through the entire vessel full insulation.  

Ohms Law:

The only electrical laws you need to know:

I (current in amps) = V(voltage in volts) / (divided by) R (resistance in ohms)

* is multiplied by sign

/ is divided by sign

To transpose the formula:
Replace letters with numbers
4 = 8 / (divided by) 2
8 = 4 *(multiplied by) 2 so V = I * R
2 = 8 / 4 so R = V / I

That’s it. Unless you want Watts (heat) = I * V

Difficulty? Contact us. 

My background and Capability Statement, click here.

Glen Bishop of SeaBis.

Suggested reading:
Corrosion CAUSE knowledge base here.

Secured By miniOrange