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Water Softener Without Salt

Scott Wilson | Posted in General Questions on

I saw this on a video from Matt Risinger. Has anyone else used it?

Apparently it uses citrus instead of salt so there isn’t that “slimy” residue feeling on your skin after a shower.

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  1. Expert Member
    Zephyr7 | | #1

    It's possible. I don't know about the ongoing operating costs though.

    Normal water softeners work by using the resin in the softener as a sort of catalyst to exchange the calcium ions in the water -- the "hardness" -- with sodium ions from the salt. The remaining chloride ions from the salt go out in the discharge from the water softener regen cycles, along with the calcium ions. Sodium doesn't make the scale, since the scale is the calcium in the hard water coming out of solution. If you check for total dissolved solids (TDS), you can see that that number doesn't change before and after the softener, since you're doing ion EXCHANGE, you're not filtering anything out -- filtration is a different process.

    The Nuvo system appears to be using citric acid, which will lower the pH (make the water more acidic), and chelate the calcium ions which binds them into a different molecule rather than swapping them with a different ion. I don't know if there are any different problems associated with water that's been treated by this process, I'm an engineer, not a chemist :-) I don't see any reason to think there would be any issue with safety though.

    The slimy feeling of softener water is due to the softened water's inability to strip the soap film away from your skin effectively. The slimy feeling is really coming from the soap. I don't know if the Nuvo system's treatement process would help with that or not.


  2. PBP1 | | #2

    I watched that tonight too, and I have one. It works to some extent but I’m concerned about carbon source and mold. When it’s got citric, I tend to see more mold in bathrooms. At P&G, we added citric acid as a chelant to detergents, and it works. But toilet tanks and residual water don’t benefit from sitting around with extra carbon (food). So, pros and cons. As a chelant (from Greek word chela for "crab's claw"), citric acid binds cations, which interfere with ionic surfactants and fatty acids (body oils). Cations form complexes with fatty acids that are extremely difficult to breakup and remove from clothing/bedsheets.

    Pros: spotting is less on chrome finish fixtures and glass/glass tiles and easier to remove upon cleaning. Likely less detergent usage as citric acid is a chelant added to many detergents (a builder) to remove hardness. Some benefit to on-demand hot water heater, though hard to discern.

    Cons: citric acid (degraded?) may be an apparent carbon source available for growth of bacteria and/or mold. Can notice growth spots in bathroom sink and around shower drain. Seems to go away when the citric cartridge is empty. As an experiment, put a couple pieces of copper tubing in the toilet tank, as copper retards growth (as in boat paint). But still need to clean the tanks once in a while.

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