Water softener for prewashing?
  • Hello everybody,

    Is it really important to add water softener when prewashing the shirts? I have a high efficiency front loader and I'm not sure how I would measure the softener. I plan to use softened water for everything else and I don't live in an area with particularly hard water.

    What's the consensus on this?

    Thanks! Diana:)
  • I don't add water softener when prewashing my fabric, but that's because I don't have hard water. If you have really hard water, you can get calcium or magnesium deposits on the fabric that cause real problems in color evenness and in dye wash-out.

    My water is just hard enough to make the sodium alginate gel in the bottles occasionally, so I always use sodium hexametaphosphate when mixing up alginate. I hate alginate gel. It's impossible to get out of the bottles. Alginate gels in the presence of calcium, and it doesn't take much.

    How much sodium hexametaphosphate would you use in a high efficiency front-load washer? It depends on how hard your water is, but there's no harm to the dyeing process in using too much. We calculated that the water in, say, Toronto, requires one teaspoon of water softener per ten liters, which is two and a half gallons. An ordinary old-fashioned top-loading washer holds about twenty gallons of water, so you'd add about 8 teaspoons of sodium hexametaphosphate to it, if your water were the same hardness as Toronto's. The total amount of water used by a old top loader ends up to be about forty gallons of water; a front loader might use about half as much total water, but less than half as much in the initial washing. So, maybe two teaspoons in the wash cycle itself.

    You can find out how much hardness is in your own water by looking at the water analysis report. This is made available for free to all users of public water systems.

  • Thank you! You are really knowledgeable!