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Rheem Marathon tank

Arnold K | Posted in Mechanicals on


Does anyone here any experience with the Rheem Marathon? 

I am considering it because I will be on a well (hard) water with sulfur and the tank is  made out of polybutene. Also the tank some with a lot more insulation but I am not sure the additional insulation warns the cost premium.

Rheem Marathon 50 Gal Lifetime Electric Water Heater | The Home Depot Canada

Thank you,

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  1. Expert Member
    Zephyr7 | | #1

    I have a membrane of the same material in my well's pressure tank, and we also have a fair bit of sulphur in the water, manganese, and calcium contributing to our very hard water and we've had no problems with the pressure tank. Pentek makes an iron removal cartridge that will also get manganese and sulphur. It's not cheap (about $70 right now, which is cheaper than the ~$85-90 I usually see), but it does an excellent job. It fits in the regular 20" "big blue" filter housings. A link to the cartridge is here:

    Note that you need to have a particulate filter ahead of the iron reduction cartrdige. I like their 2501 filter that goes from 25 microns on the outside to 1 micron on the inside -- this particulate filter can trap a lot more sediment before it becomes so clogged that it doesn't work well anymore.

    If you have a lot of sulphur or iron in your water, one of the backwash type iron/sulphur filters that looks like a water softener will be a lot cheaper to operate over time compared to the iron reduction cartridge I mentioned above. In terms of "greeness", the backwash type filter doesn't require disposable cartridges, either -- the media is usually said to be good for around 10 years.


  2. John Woloshyn | | #2

    Arnold, I installed one of these recently in our home. I felt that the higher relative price tag was more related to the lifetime warranty and the fact that you don’t have to worry about the tank developing a leak after several years (as opposed to the “higher insulation value”) and the related damage that can cause, not to mention the inconvenience and costs of clean up, removal and replacement when it does fail. For me, it was a no brainer.

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