Why Your Dishwasher Can't Clean Like it Used To

There’s a common misconception that dishwashers aren’t as good as they used to be. Compared to their predecessors, today's dishwashers are quieter, use less water, and seem to leave more cloudy deposits on some dishes. So what gives?

Well, there's a valid argument to be made that it is actually harder to get your dishes sparkly-clean in a dishwasher—but it has almost everything to do with detergent.

In 2010, the active ingredient in dishwasher detergents fundamentally changed. Environmental concerns pushed the industry to stop using a particularly effective but ecologically hazardous compound, known as phosphates. When these abrasive salts leach into water supplies, they can cause disruptive algal blooms.

But there’s no denying that phosphates are great at removing dirt stains and, perhaps more importantly, keeping food soils off of dishware during a wash. That’s not to say phosphates’ environmental impact was worth it, but an effective alternative for detergents has yet to be found.

Now, the industry is working mainly with enzyme-based detergents, which quite literally eat away at food soils instead of knocking them off, like phosphate salts do. These ingredients are better for the environment, but are less effective, which in turn has consumers the impression that the dishwashers themselves have gotten worse.

That seems very unlikely, as dishwasher manufacturers continue to refine the washing tech and experiment with new possibilities. Some ideas include steam power, modular designs, and even machines that don't use detergent. Bosch even has a line of dishwashers that use a super-mineral to rapidly dry dishes after a wash cycle. So innovation isn't dead, and in any case, dishwasher designs didn't suddenly backtrack 30 years after phosphates were banned. This stumble falls squarely on the shoulders of new detergents.

So how can you make do in this enzyme-based world? Try using powder detergents. Their abrasive nature makes them somewhat more effective than gel or liquid solutions at cleaning food deposits. Also, since enzymes act directly on food, don't bother pre-rinsing your dishes. That leaves less organic material for the enzymes to eat, and can in turn lead to etching—that cloudy residue on clear dishware.

If you've decided that you can't live without phosphates, and you can live with the possibility of algal blooms on your conscience, you can mix your own phosphate-based detergent. The salts are often available at hardware stores. Be sure to check whether phosphate detergents are banned in your state.