How to Clean a Cat Water Fountain Filter Unit
By PETKIT UK | Published: 2026-10-17
Category: How-to Guides
Learn the correct steps to clean and replace your cat water fountain filter unit, including specific tips for PETKIT Filter Unit 3.0 and RECT models.
Quick answer
To clean a cat water fountain filter, you need to replace the filter unit every 2–4 weeks and rinse the fountain parts weekly. For PETKIT Filter Unit 3.0, always soak the new filter in clean water for at least 10 minutes before installation and reset the device afterward.
Why regular filter maintenance matters
A dirty filter can trap bacteria, reduce water flow, and make your cat less inclined to drink. Regular cleaning and replacement keep the fountain running quietly and the water fresh, which encourages your cat to stay hydrated and helps prevent urinary issues. The PETKIT Filter Unit 3.0 uses a high density micropore filter and double filter components to remove impurities, but these need timely replacement to stay effective.
What you need before you start
Gather a new filter unit (such as PETKIT Filter Unit 3.0 or Filter Unit RECT), clean water, a soft brush, and mild dish soap. Avoid abrasive cleaners or scrubbing pads that can scratch the fountain surfaces. For PETKIT fountains, always use the correct replacement filter: Filter Unit 3.0 works with EVERSWEET2, EVERSWEET2S, EVERSWEET3, EVERSWEET3 PRO, and EVERSWEET SOLO, while Filter Unit RECT is compatible with EVERSWEET Max (Cordless).
Step-by-step filter cleaning and replacement
- 1. Unplug and disassemble the fountain: Turn off and unplug the fountain. Remove the water tank, pump, and any removable parts. Discard the old filter unit. Common mistake: forgetting to unplug the pump can cause electrical shock or damage.
- 2. Clean all parts except the filter: Wash the fountain base, tank, and pump with mild dish soap and warm water. Use a soft brush to remove debris from the pump inlet and impeller. Rinse thoroughly. Checkpoint: ensure no soap residue remains, as it can foam in the water and upset your cat.
- 3. Soak the new filter (PETKIT Filter Unit 3.0 only): Submerge the new Filter Unit 3.0 in clean water for at least 10 minutes before installing. This activates the filter media and removes trapped air. Common mistake: skipping the soak leads to reduced water flow and noisy operation.
- 4. Install the new filter and reassemble: Place the soaked or dry filter (depending on model) into the filter slot. Reattach the water tank, pump, and lid. Ensure the silicone seal ring is seated properly to prevent leaks. Checkpoint: a misaligned seal ring is the most common cause of fountain leaks after cleaning.
- 5. Reset the filter reminder (PETKIT models): After reassembly, reset the device according to your fountain's instructions. For PETKIT fountains, this usually involves pressing and holding a button until the indicator light changes. Common mistake: forgetting to reset the reminder means you won't know when the next filter change is due.
- 6. Run a test cycle and check for noise: Fill the fountain with fresh water and plug it in. Let it run for a few minutes. Listen for unusual pump noise or gurgling, which can indicate air trapped in the system. If noise persists, repeat the soak step or check the pump for debris.
Products mentioned in this guide
- Filter Unit 3.0 -5pcs: PETKIT filter for EVERSWEET2, EVERSWEET2S, EVERSWEET3, EVERSWEET3 PRO, and EVERSWEET SOLO. 5 pieces. With double filter components and a high density micropore filter. Silica gel sealed ring with lock key design. ATTENTION: Please soak the new filter for at least 10 minutes in clean water before installing into the fountain. Please do not forget to reset the device after the replacement. Soaking the filter prevents air bubbles from blocking water flow, and resetting the device ensures the filter life indicator is accurate.
- Filter Unit RECT 5PCS: PETKIT Smart Pet Drinking Fountain Filter Unit RECT, Replacement filter for pet water fountain. It is compatible with PETKIT Eversweet Max (Cordless) pet water fountain. Multi-layer filtration system brings fresh and clean water and helps to keep your pet free from urinary diseases. The multi-layer filtration system removes more contaminants than single-layer filters, making it a good choice for homes with multiple cats or hard water.
