Aluminum vs Magnesium Anode Rod in 2022!

Is your heater doing its job? If not, then your anode rod is to blame! The selection of the appropriate anode rod should naturally be of the utmost importance.

Wondering which one works better between aluminum vs magnesium anode rod?

If you’re using the water heater for drinking water, magnesium anode rod is best. But aluminum rods provide faster heating and last longer. But its residue buildup is more and is hard to install. Magnesium rods works well in soft and chlorine water and has little-to-no side effects.

aluminum vs magnesium anode rod

This is just the tip of the iceberg. There are lots that you need to know before you make a sound decision.

Don’t let your mind get thrown off! If you’re unsure about which anode rod is best for your application, we’ve put together a comprehensive guide here.

Quick Overview: Aluminum vs Magnesium Anode Rod

 Aluminum Rod Magnesium Rod
IdentificationBends EasilyDoesn’t Bend
EfficiencyFaster HeatingSlower Heating
Cost$20 – $50$40 – $100
PropertiesWorks well in Hard WaterWorks well in Soft Water
Residue BuildupMore SedimentLess Sediment
Water Tank DeteriorationFastSlow
Replacement FrequencyEvery 4-5 yearsEvery 2-3 years
Installation DifficultyHardEasy
Side EffectsExtensiveModerate

Through Discussion: Aluminum vs Magnesium Anode Rod

Knowing which sacrificial rod to use in your water tank is crucial. Therefore, we’ve set up a stark distinction between the two types of anode rods.

Let’s get this done without wasting more time!


To find out which anode rod is used in your water heater, you can check the heater manual. If it’s not mentioned in the manual, you have to take out and inspect your anode rod.

1. Aluminum Rod

Take a rod out of your water heater and examine it to determine if it is made of aluminum or another material. Try bending the anode rod.  If the rod can be bent with little effort, then the material is likely aluminum.

2. Magnesium Rod

If your rod doesn’t bend, it is probably made of magnesium. If you want more proof, you can check it on your own. Most anode rods have their names written on the unit’s top. A hex screw is used to secure the rod in position. Once the rod has been loosened, you should be able to see the labeling on it.


The ionic strength and water quality will determine not only the effectiveness of your anode rods but also what settings work best for your water heater. However, there are some details about the individual rods that you should be aware of.

1. Aluminum

Since aluminum rods don’t react as much, they last longer. These anode rods are stronger because they are made of both aluminum alloys and a zinc metal. They are without a doubt very efficient, but you shouldn’t use them for drinking water heaters.

Aluminum rods take far too long to react when placed in ice water. to the point where it might not be possible to avoid deterioration in the extreme. The smell of metal can be eliminated when water comes into contact with these rods.

2. Magnesium

Magnesium rods offer excellent corrosion resistance. Although they are prone to corrosion in hard water, they are beneficial to human health in the long term. In addition, magnesium diluted in water has health advantages.


The price of the rods depends on the length and requirements of your heater. Let’s see which one is more cost-effective, shall we?

1. Aluminum

Aluminum rods are typically a less expensive option.Compared to magnesium, it is less exorbitant, and doesn’t generate as much hydrogen peroxide. The cost of replacing an aluminum anode rod is typically in the range of $20 to $50.

2. Magnesium

Despite the fact that magnesium and aluminum are both fairly common on earth —, magnesium seems to be harder to come by. And it’s so costly to process and refine it. The price range could be anywhere from $15 to $100, depending on the features included. Flexible ones are more expensive.


Now, we’ll discuss the working medium of the individual anode rods.

1. Aluminum

For residences with hard water and an elevated PH, aluminum rods are suitable. Rapid corrosion of magnesium rods occurs in hard water.

2. Magnesium

Using magnesium rods in soft as well as alkaline water is a no-brainer. There are lesser electrolytes in soft water. Utilize this rod in situations where your water contains high concentrations of chlorine. Magnesium eliminates chlorine.

If your home has an effective filtration system, the magnesium anode rod is a good choice. Anode rods made of magnesium are more susceptible to attack by sodium ions. So, they’ll protect your drinking water.

Residue Buildup

You’ll notice that deposits will continuously accumulate at the very bottom. This happens when one of the anode rods rusts.

1. Aluminum

Aluminum sediment accumulation can end up causing your water heater to operate noisily.   Sediments can impede the effectiveness of your boiler if they accumulate for an extended period of time. Furthermore, aluminum anode rod debris is a possible health hazard.

2. Magnesium

Due to the increased bicarbonate in your water, a few scales may form in the water reservoir. Magnesium anodes can effectively lessen most of these scales.

Magnesium actually at times prevents depositional formation. They produce no harmful sediments. Furthermore, the magnesium sediments are easier to clean up.

Water Tank Deterioration

Even with a thriving anode rod, your boiler may begin to rust over time.  So, you need to figure out which anode works best for you.

1. Aluminum

Aluminum anode rods may not be able to withstand the corrosive demands of your water heater. Extreme sediment can cause cloudiness in your heated water. The tank will corrode and deteriorate more quickly as a result of this.

2. Magnesium

Magnesium electrodes are more resistant to corrosion. Using these rods will help you get more use out of your water heater for a longer period of time. As a result, magnesium anode rods have a longer useful life.

Replacement Frequency

We’ll talk about the average lifespan of these rods. Nevertheless, this is something that can change based on how often water is heated by a water heater.

1. Aluminum

The lifespan of these rods is significantly longer. Anodes must be altered every four to five years on average.

2. Magnesium

Magnesium has a higher reactivity. They produce more voltage, but this contributes to their deterioration. The magnesium rod should protect against rusting for about two to three years.

Installation Difficulty

The installation difficulty can depend on the amount of sediment formation. Let’s have a look and decide what’s best for you.

1. Aluminum

A swollen aluminum rod is a sign of deterioration. This is what’s causing them to squeeze into their spaces so rigidly. The removal of aluminum anodes that are more than a few years old can be extremely difficult. It is very hard to take out and put in aluminum rods.

2. Magnesium

Magnesium doesn’t swell. Removing and replacing them is usually a simple process. To install these rods, you just screw them in.

Side Effects

1. Aluminum

Aluminum is considered by most people to be less dangerous than other toxic metals. But in large amounts, it can be dangerous. Aluminum deposits infect the abdomen, nerves, digestive system, and urinary tract. Furthermore, if rust falls into faucets, it can induce leaky pipes.

On occasion, you will observe a gray or turquoise gel at the base of your hot water anode rod or in the reservoir. Aluminum anode rods respond with elevated chlorine content in water and generate aluminum hydroxide.

2. Magnesium

Magnesium is good for your body. It has a variety of other benefits, including lowering blood pressure.

Corrosion Prevention

You can prevent the corrosion of your water tanks caused by the anode rods by fallowing these tips.

Glass Sealing:

Glass sealing material should be used to line or wrap your water storage tanks. Because of this lining, the metal of the tank does not come into contact with the water. However, there are some imperfections in the glass protective layer. Pores or flaws in the glass sealant could allow water into the steel beneath.

Powered Anode Rods:

For relatively larger reservoirs and longer pipelines, powered electrodes can be substituted. The metals are protected from damage by using an electrical power supply.


Rods made of magnesium and aluminum are widely available. But some of them are easier to get than others.

1. Aluminum

After learning about the damaging impacts aluminum has had on our brains and bodies, aluminum use has decreased significantly. They can still be used where tap water isn’t consumed.

2. Magnesium

Currently, magnesium electrodes are perhaps most prevalent. Almost all water heaters for human consumption make use of them.

Which One is Better?

We can state that both rods are suitable for use in whatever water heater that you have. But there are still considerable distinctions between them that you should be aware of.

If you’re heating your water for regular use and for drinking, magnesium is the best choice. They corrode faster but they’ll protect your health.

Laundry establishments can utilize aluminum anode rods. However, in the long term, it produces a rotten egg odor. If you’re on a tight budget and don’t intend to drink the water, these rods are a suitable decision.

Frequently Asked Questions

Is the size of the anode important?

Answer: Yes, the size of the rod matters. The greater the amount of magnesium or aluminum on the anode, the longer your hot water canister will be protected. It also depends on what kind of water heater you have.

How do I figure out what length anode rod I need?

Answer: Your water heater manual should have the size of anode rod you’d need. Evaluate the tank’s length and choose the nearest electrode size if you don’t have the manual. Too-long electrodes can be cut with a power drill.

Final Thoughts

Now you can clearly see the difference between aluminum vs magnesium anode rod. All you have to do is decide on which anode rod you’d need.

A word of advice: Verify with your water heater manufacturing company. Because the water tank cylinder is sometimes lined. In that scenario you might not need an anode rod.

Wishing you luck with your endeavors!