Dishwasher Leaving Dirty Streaks on Glass

dishwasher glass marked

You expect your dishwasher to do a better job at cleaning dirty dishes than you ever could by hand, and if you operate them correctly, they will. But lately, you’ve noticed that your glasses are becoming cloudy with white deposits, and streaks.

There are a few possible causes for this residue that’s appearing on your glassware – mentioned below, and further into this article we’ll talk about prevention methods.

Possible Causes:

  • Lime stains
  • Salt deposits
  • Glass corrosion

Limescale Stains on Dishes and Glasses

White limescale residues on dishes and glasses are common in hardwater areas. Some dishwasher tabs contain a water softener that can help to tackle this problem. With that said, some of the natural dishwasher tablets are phosphate-free which can also lead to white marks appearing, so it’s wise to do your research into the detergent you’re using.

If you live in a hard water area, then you really need to fill your machine with dishwasher salt, as this works to soften the water going into the machine.

How to remove limescale stains from glass: This can be tricky, but many people have found vinegar, hot water, rubbed with a soft cloth to be very effective.

Check to see whether you live in a soft or hard water area so that you can optimise your dishwasher in a way that will soften water, reducing those white limescale marks.

Salt Deposits

White spots on the dishes are tricky at first glance: you don’t know straight away whether it is limescale or salt deposits. There is almost no visual difference.

While limescale residues are a bit more stubborn, salt deposits can be washed off easily with water without any problems. That’s how you test – limescale stains are hard to remove, while salt can easily be wiped away with a damp cloth.

  • Do the stains persist? Then lime is likely to spoil the dishes.
  • Do the stains wipe away easily? Then you are dealing with salt deposits.

Potential Causes of Salt Deposition:

  1. Too much salt in the dishwasher.
  2. Using the wrong type of salt in the dishwasher
  3. Salt compartment does not close properly.

Check that the lid of the salt container has seal and is properly closed. In addition, you should always ensure that there is a reasonable amount of salt in the container (not too much, but also not too little). Finally, check to make sure that you’re using the correct salt – not table salt or some cooking salt.

Glass Corrosion

If you cannot remove the milky white marks from glasses and pieces of cookware made of glass, despite your best efforts, then you could have a glass corrosion problem. Unfortunately, this fine abrasion removes the smooth shiny layer of glass and leaves a permanent mark – think of how an old piece of broken glass looks, washed up on a beach.

Glass corrosion can be identified from other problems with close inspection. As a rule, it does not affect the entire glass, but rather specific areas. The centre of the glass is usually particularly badly affected. In this area, glasses tend to collide when they are washed in the machine if they are close together. This speeds up the corrosion process.

Normally, glass corrosion does not arise from one moment to the next. Rather, it gradually becomes ware away at the glass over time. What this means for you: If your glass collection is important to you, or valuable, you should wash it by hand right from the start.

Note: Even very high temperatures in the dishwasher promote the development of glass corrosion. It is therefore advisable to clean glasses – if not by hand – at least on your own (without any other dishes) using the dishwasher’s special glass cleaning program.

As mentioned, if the glass is corroded, there is nothing that can be done to reverse this, and new glasses will have to be purchased to replace them.

Always read the packaging of new glasses and glass dishes. There it is written whether they are dishwasher safe or not. In addition, it is important to clean glasses in the machine at the lowest possible temperature and in the shortest possible time. Remove the items of crockery immediately after the wash cycle. This means that they are not exposed to steam for too long, which can attack the surface.

In addition to glass corrosion, there are other causes of streaks on glass. They can be conveniently divided according to colour.

  1. Whitish stripes = limescale deposits (fixable) or glass corrosion (not fixable).
  2. Bluish / metallic streaks = too much rinse aid in the machine.

Rinse aid streaks are very difficult to remove from glasses. Unfortunately, you won’t get very far with soap and water. Trying rubbing the glasses down with vinegar, even let them soak in a mix or hot water and vinegar for 20 minutes, then rinse the glasses thoroughly. At best, the streaks will then have disappeared.

Avoiding Milky Dishwasher Streaks

Do you have very soft tap water in your area? Then you do not need to use a rinse aid. This way you protect your glasses and your wallet.

Do not put additives such as water softener, regeneration salt, rinse aid or glass protection in the form of purpose tablets, but rather separately in the dishwasher. When everything is combined in one tab, the mix may not be optimal.

Other Stain Causing Problems

Outside of the white milky, cloudy steaks on your glasses, you may find other cleaning related issues with your dishwasher. If whole pieces of food are still hanging on the plates and cutlery, there is often a simple reason: incorrect loading, which is easily resolved by learning how to load a dishwasher for best results. If dishes are too close together, detergent and water will not get to the right places.

Do not overfill your machine and follow the motto when putting it away: “Creative chaos is better than strict order”. That means in plain language: The plates should never be stacked, think sensibly as ask yourself – will the jet nozzle be able to spray these dishes.