PETKIT Foam Filter vs Filter Unit 3.0: Which One Do You Need?

By PETKIT UK | Published: 2026-10-15

Category: Comparisons

Compare PETKIT's Foam Filter 15pcs and Filter Unit 3.0 to see which replacement your fountain needs, how they differ, and when to swap each one.

Quick answer

The PETKIT Foam Filter 15pcs is a pack of fifteen foam filters that capture debris and keep water clear in PETKIT water devices. The Filter Unit 3.0 is a five-piece filter set with double filter components and a high-density micropore filter, compatible with EVERSWEET2, EVERSWEET2S, EVERSWEET3, EVERSWEET3 PRO, and EVERSWEET SOLO. Buy the Foam Filter if you need a bulk supply of foam inserts; buy the Filter Unit 3.0 if your fountain uses the full filter unit and you want the micropore filtration and sealed ring design.

What each filter actually does

The Foam Filter 15pcs is a straightforward maintenance item: fifteen foam filters that snap in easily and capture debris to help keep water clear and hygienic. It is designed specifically for PETKIT water devices, so it is the right choice when your fountain uses foam inserts as part of its filtration. The Filter Unit 3.0 is a more complete replacement: each unit includes double filter components and a high-density micropore filter, plus a silica gel sealed ring with a lock key design. That combination is aimed at fountains that rely on a sealed filter unit rather than a simple foam pad.

Compatibility: which one fits your fountain

The Filter Unit 3.0 is explicitly listed for EVERSWEET2, EVERSWEET2S, EVERSWEET3, EVERSWEET3 PRO, and EVERSWEET SOLO. If you own one of those models, this is the filter unit designed for your fountain. The Foam Filter 15pcs is described as specifically compatible with PETKIT water devices, but the catalog does not list individual fountain models. That means you should check your fountain's manual or the filter slot itself before ordering the foam pack. If your fountain uses a full filter unit with a sealed ring, the Foam Filter alone will not replace it; if your fountain uses foam pads, the Filter Unit 3.0 may not fit.

Replacement timing and maintenance

The Filter Unit 3.0 requires a simple but important step: soak the new filter for at least 10 minutes in clean water before installing it, and reset the device after replacement. Skipping the soak can affect performance, and forgetting the reset means your fountain may not track the new filter correctly. The Foam Filter 15pcs is a snap-in replacement with no soak mentioned, so it is quicker to swap. For either filter, replace when you notice debris buildup, reduced water clarity, or a change in flow. The 15-pack gives you a longer supply between reorders, while the 5-piece Filter Unit 3.0 pack covers five changes.

Cost and convenience trade-off

The Foam Filter 15pcs comes in a larger pack, which can mean fewer reorders and a lower cost per filter if you change foam frequently. The Filter Unit 3.0 comes in a 5-piece pack and includes more complex components, so the per-unit cost is higher, but it delivers the micropore filtration and sealed design that some fountains need. Neither is universally better; the right choice depends on which filter your fountain uses and how often you replace it.

Trade-offs at a glance

Foam Filter 15pcs: bulk supply vs. simple filtration: You get 15 foam filters and quick snap-in changes, but the foam is a debris-capturing layer rather than a full filter unit with micropore filtration and a sealed ring. Choose this if your fountain uses foam pads and you want a long-lasting pack.
Filter Unit 3.0: full filtration vs. higher unit cost: Each unit includes double filter components, a high-density micropore filter, and a silica gel sealed ring with lock key design, but you get 5 pieces and must soak each new filter for 10 minutes and reset the device. Choose this if you own a compatible EVERSWEET model and want the complete filter unit.
Compatibility: model-specific vs. general: Filter Unit 3.0 lists exact fountain models; Foam Filter 15pcs is listed for PETKIT water devices generally, so you need to verify your model uses foam inserts. Check your fountain's filter type before buying either.

Product facts

Foam Filter 15pcs: Contains 15 foam filters per package, easy snap-in replacement, effectively captures debris to keep water clear, and is specifically compatible with PETKIT water devices. A 15-pack suits owners who replace foam filters often and want a ready supply without reordering each time.
Filter Unit 3.0: PETKIT filter for EVERSWEET2, EVERSWEET2S, EVERSWEET3, EVERSWEET3 PRO, and EVERSWEET SOLO; 5 pieces; double filter components and a high-density micropore filter; silica gel sealed ring with lock key design; soak for at least 10 minutes before installing and reset the device after replacement. This is the correct replacement for those specific fountain models, and the soak-and-reset steps are required for proper operation.

Which one should you buy?

Best for

Owners of EVERSWEET2, EVERSWEET2S, EVERSWEET3, EVERSWEET3 PRO, or EVERSWEET SOLO who need the full Filter Unit 3.0 replacement.
Owners whose PETKIT water device uses foam filters and who want a 15-pack for frequent changes.

Not for

Fountains that require a full filter unit with a sealed ring — the Foam Filter 15pcs alone will not replace it.
Fountains that use only foam pads — the Filter Unit 3.0 may not fit or be necessary.