Does your trusty dishwasher actually need all that soap? Probably not.

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Many of us do a lot of things without thinking too much about them. Putting soap in the dishwasher is one of those. Most people will just fill the dishwasher's soap container, or fill the cup that came with the box in the case of powdered soap, and that's it. Few people read the dishwasher's instruction manual or even those on the soap container.

It's only a small thing, though. It can't matter much, right?

Well, that's not quite how it works. To measure the environmental impact of something, you also need to take into account the frequency. If you use your dishwasher every day for pretty much the rest of your life, that's a lot of soap! Just imagine what a mountain all those soap bottles would make if you could see them piled up all at once.

What if you could reduce that mountain by a significant amount (maybe by half or more, depending) without affecting how clean your dishes are? That's what many could do if only they took the time to read the instructions.

How effective soap is depends on the 'hardness' of your water (how much dissolved minerals are in it). If your water is very hard, you might need to actually fill the soap cup completely, but in most other cases, a lot less soap is required. In fact, with soft water, as little as one tablespoon (or less with concentrated soap) is required.

Image that mountain we talked about earlier shrinking vastly! And you'll also save a lot of money on soap over a lifetime as a side effect of helping the environment.

So here's your homework to figure out how mush dishwasher soap you should use:
  • Call your water company and ask about water hardness in your area.
  • Read your dishwasher's instruction manual and the instructions on your soap to find out how much soap you really need.
  • If you don't already, make sure to buy soap that is phosphate-free, biodegradable, and that comes in a recyclable container. Bonus points if you can find more concentrated soap (regular soap has a lot of filler that takes space and adds weight, making it more polluting to ship).

Now how about experimenting with using less shampoo, toothpaste, etc.?