Troubleshooting:
What is the water filter sponge?
Why to use: Capture and filter fine impurities and particles, to improve humidifying efficiency in a healthier way.
When to change: Generally lasts 1 month depending on hardness of water.
Where to buy: Please search B09ZY9N6PD or LEVOIT 10-Pack Humidifier Replacement Filters on Amazon.
Note: Distilled/ purified water is preferred for your health.

Specifications:
Product Dimensions: ‎9.7 x 8.1 x 13.4 in / 24.5 x 20.5 x 34 cm
Whisper-Quiet Operation: ≤ 30dB
Effective Range: 215-505 ft² / 20-47 m²
Material: BPA free, suitable for babies and adults.