Can I just put a bunch of magnesium in the tank instead of an anode?

[FishScreener]

If the electrode is really corroding in three weeks, you have something else going on. Not sure what is driving the reaction, but something is seriously wrong. Is you water supplier impressing current as part of a corrosion system? I was serious when I said I’ve never had an element fail for any reason other than operator error.

 

[chiraldude]

Here is the deal about the cathode/anode thing. When you have 2 different metals in contact, you get a voltage that tries to make current flow through the water. It's like half of a battery. Magnesium is chosen because it will create a voltage ever so slightly higher than the iron of the tank. This slight voltage causes the oxygen in the water to favor the Magnesium over the Iron. The result is that the Magnesium slowly oxidizes and zero iron in the tank oxidizes until the rod is gone. At first, there is hardly any Iron available because of the glass lining of the tank so the rod corrodes very slowly. Eventually cracks develop in the lining which exposes some tank metal which allows current to flow between the two metals. That's why you should check the rod once a year after the tank is about 5 years old.

 

[Jamesplumbing06]

bottom line its your tank. It will only last 10-11 years max. Do as you please. But a 1.25” socket with impact will bring the old one out. Or pull the hot line and get a hot line anode rod. What your trying to do might work. Or it may rust tank anyways. Most anode rods go away quickly if your water is going to eat it. Me personally. A tank that has been I long enough to eat that rod. Is usually old enough to let ride. I have replaced busted tanks with the anode fully intact. I think somebody just woke up wanting to argue. If you don’t accept a plumbers opinion then move on to engineering forum. People don’t run around checking the anode rod. We as professional have a code book. We follow and give advise according to that code. You wanna go rougue go ahead. You won’t loose your liscence.

 

[mike fiore]

if shoving magnesium in the tank was an option they would of put a door in tank to open and add magnesium. If you follow manufactures maintenance schedule i have seen tanks last 15 to 20 years with no problems. get the replacement anode and change the old one out. some tanks have an extra anode kit which will give you a ten year warranty. if you dont believe us call tech support from manufacturer. also if you have a element corroding in 3 to 5 weeks you have something else going on. either electrical or person who put tank in turned electric on before filling and purging tank.