Air Bubbles in the water:

The white particles you are seeing most likely are tiny air bubbles, they usually appear when you replace new filters. You can use magnifying glass to see them, they are air bubbles. If they are white particles, they will sink to the bottom. The filters do not have any white particles. The air bubbles would gradually disappear after 2 weeks. If you don't want to have air bubbles in your cup, you can try opening the dispensing faucet for 2 seconds before you catch the water.