Replacing anodes - too many ?

I have 4 anodes on the boat, 2 on the rudder and two connected up to copper wire that is connected to other metal parts.

The two that are connected with copper wire had some white coating (like limescale). Does this mean that the connections were not good ?

I have boat a new one shiny anode and have cleaned up the other two as it looks like they are only about 10 % depleted.

Is there any problem with having too many anodes - would it set up wrong currents or something ?

Obviously too many anodes ( like 100 ) would sink the boat ! - so I am asking about the electrics. They are called sacrificial anodes - so with more doesn't the sacrifice just get spread over several of them and happen more slowly ?

Thank for any advice.

Dave.

 

The limesaclae covering is normal errosion.

You have enough anodes if the part you are protecting is protected ie in good shape.

However you can not over anode. its just more drag.

Your rudder should be bonded to the other anodes too. However after saying that there are two ways of thinking on this.

Some prefer to seperate each item with its own system of protection. On the other hand some say that if you are permenantly in a marina, a huge bonding system with ALL anodes connected can actually gather stray currents!!!!. Up to you.

You could if you wanted temporary protection, attach a anode to a piece of wire and attach that to the part you are protecting ( shaft) and throw the anode over the side.

This has many benefits such as you can easily maintain and observe errosion.