White marks usually mean hard water, low rinse aid, or detergent not dissolving properly.
Common causes
- Hard water
- Low rinse aid
- Too much detergent
- Blocked spray arms
1. Hard water
Minerals leave chalky residue.
Quick fixes:
- Add rinse aid
- Use dishwasher salt
- Try a hard‑water detergent
2. Low rinse aid
Helps water slide off dishes.
Quick fixes:
- Refill rinse aid compartment
- Increase the dosage setting
3. Blocked spray arms
Food bits stop water reaching dishes.
Quick fixes:
- Remove and rinse spray arms
- Clear blocked holes with a toothpick
What to try first
Refill rinse aid — it’s the fastest improvement.
When to call a professional
If dishes stay cloudy even with salt and rinse aid.