Different Types of Anodes

Posted on: 13 October 2017


Submerged metals can corrode as they may react when in contact with water. This may affect some systems such as your home water heater from operating efficiently or even breaking down. To prevent this, anodes are used to prevent corrosion instead of the submerged metal being oxidized by water. There must be contact between the anode and metal being prevented from corrosion as well as the water and the anode for electrons to pass through. There are different types of anodes depending on the type of environment you want to use them in. They include aluminum, magnesium and zinc anode.

1. Aluminium anode — This type of anode is most suitable for environments with hard water. It was adapted in the olden days and is mostly found in traditional water heating systems. However, aluminium poses a health threat to those who come into close contact. It is advised not to drink water from tanks that use aluminium anodes. They are cheap and thus preferred by many. It goes without saying that the level of protection provided by aluminium anodes is of the lowest quality and may last only up to a half a decade. The corrosion also builds up on aluminium as time passes by. 

2. Magnesium anode — It is preferred in areas with soft water. It is also the most commonly used type of anode. Magnesium anodes rank better than aluminium ones when it comes to preventing rust and thus more expensive. It also does not pose any health problems to those around making it a desirable choice. The downside is that magnesium anode corrodes fast thus giving them a short lifespan. You will need to replace them every now and then. Magnesium anodes also give a nasty smell when they react with water that has bacteria. If this is the case, you may have to select a friendlier anode for your type of water.

3. Zinc anode — Zinc can also be added to an aluminium anode, but it will occupy just a small portion of it. This is especially essential when it comes to combating the odour that comes from sulphur that can be found in tanks. It is a perfect step to combat the smell instead of entirely doing away with the anode. They are not factory-installed but can be added later on when the need to arises. Combining zinc and aluminium is costly making it the most expensive option when selecting an anode.