Frequently Asked Questions (FAQ) Q1: How often should I replace the filter? A: Replace every 70 liters of water or every 2 months, whichever comes first. Replace sooner if have hard water. Q2: How do I know it's time to change the filter? A: Replace the filter if notice: (1)Limescale buildup (2)Bitter or unclear coffee flavor (3)Slower water flow or louder operation (4)Even without signs, regular is . Q3: Is it compatible with LELI machine? A: Yes, this filter is compatible with LELI espresso machines. Q4: What does the filter do? A: It softens water by replacing calcium and magnesium ions with sodium, helping prevent scale and improving coffee taste. Q5: How do I install the filter? A: Remove the water tank, take out the old filter, and insert the new one. Ensure it's fully submerged and securely connected. No tools needed. Q6: Can I reuse the filter? A: No. The resin is not reusable. use a new filter for results. Specifications: Compatible: Compatible with LELI machines frequency: Replace every 70L or 2 months Material: Resin Length: 5.91 Inch Diameter: 1.38 Inch Package includes: 2 x Cationic Resin Filter for Water Tank Notes: 1. Do not use distilled or pre-softened water with the resin filter, as it may reduce ion exchange effectiveness. 2. If the machine not be used for an extended period, remove and dry the filter to prevent resin aging. 3. For convenience, attach a date label to the water tank as a reminder.