Your Dolphin robotic pool cleaner works hard every cycle, but even the best robot needs a clean filter to keep your pool sparkling. Over time, original filters wear out, lose efficiency, or just get too clogged to rinse clean. That is where Dolphin aftermarket replacement filters come in. They offer the same or better filtration at a fraction of the cost of OEM parts. Whether you own a Dolphin Nautilus CC Plus, Active 20, S200, or M400, there is a compatible replacement that will restore your cleaner’s suction and capture even the finest debris. In this guide, we have evaluated eight top-rated aftermarket filters, comparing build quality, compatibility, and filtration performance to help you make a confident choice for 2026.
If you are new to pool robot maintenance, you might also want to check out our guide to Dolphin fine filters for a deeper look at how different filter types affect water clarity.
Pros
- High-efficiency microfiltration captures fine dirt, sand, and leaves for pristine pool water.
- Works with a wide range of popular Dolphin robot models, reducing the need for multiple filter types.
- Easy to clean and maintain with no special tools required.
- Affordable price compared to manufacturer replacement filters.
- Solid build quality with lightweight yet sturdy plastic construction.
Cons
- Not compatible with Dolphin Nautilus CC Pro or CC Supreme models, limiting its use for newer variants.
- Older versions of Active 10 or S50 may require removal of a plastic piece for proper fit, which could be inconvenient for some users.
- As an aftermarket part, it may not perfectly match OEM quality or warranty coverage.
The Ulticor Ultra Fine Filter Basket is an aftermarket replacement designed specifically for a wide array of Dolphin robotic pool cleaners. It is an ideal choice for pool owners who already own compatible models such as the Dolphin S50, S100, Active 10/15, Echo, T15, T25, Proteus DX3, Saturn, Cayman, Escape, and others. This basket is not intended for the Nautilus CC Pro or Supreme versions, so buyers should verify compatibility before purchasing.
What sets this filter apart is its microfiltration technology, which captures even the tiniest debris particles. In real-world use, this translates to a noticeably cleaner pool with clearer water, as fine dirt, sand, and pollen are effectively trapped. The basket is easy to rinse and clean every four to six weeks, maintaining peak performance without hassle. Users report that it fits snugly and works reliably cycle after cycle.
The design is straightforward: a white, lightweight plastic basket measuring roughly 9x5x7 inches. Build quality feels solid for an aftermarket part, though it may not have the exact finish of an OEM component. The inclusion of installation tips for older Active 10 or S50 units (which may need a small internal plastic piece removed) shows attention to compatibility details. A video guide is available upon request to assist with that adjustment.
Potential drawbacks are mostly centered on fitment limitations. Owners of Nautilus CC Pro or Supreme will need to look elsewhere. Also, the need to modify older robots could be a minor inconvenience for those not comfortable with simple DIY tasks. However, for the vast majority of compatible users, installation is plug-and-play.
Overall, the Ulticor Ultra Fine Filter Basket offers excellent value for money. It delivers superior filtration at a lower price than official replacements, while covering a wide range of popular Dolphin models. If you own one of the listed robots and want to keep your pool sparkling clean without breaking the bank, this filter is a smart buy.
Pros
- Ultra-fine filtration traps even tiny particles for superior water clarity.
- Easy numbered installation system reduces setup time and guesswork.
- Washable and reusable design offers long-term value and eco-friendliness.
- Broad compatibility with many Dolphin and Maytronics robotic pool cleaner models.
- Sturdy build quality withstands regular use and cleaning without tearing.
Cons
- May require more frequent cleaning than standard filters due to ultra-fine mesh trapping more debris.
- Not compatible with all Dolphin models; double-check compatibility before purchase.
- Some users may find the initial fit slightly tight on certain cleaner baskets.
The Henkgo ultra-fine filter panels are a direct replacement for the OEM part 9991467-R4, designed specifically for Dolphin robotic pool cleaners. These pleated cartridge filters are ideal for pool owners who want to maintain sparkling water without frequent skimming. They fit a wide range of models including the S200, Active 20, Proteus DX4, M600, and many more, making them a versatile upgrade for most Dolphin owners.
Standout features include the ultra-fine pleated material that captures sand, gravel, leaves, and even microscopic debris. In real-world use, these filters dramatically improve water clarity compared to standard mesh filters. The numbered panels (1-4) simplify installation: remove in order and replace in reverse, so even first-time users can swap them in minutes. The filters are also washable with a garden hose, retaining their shape and effectiveness after repeated cleanings.
Build quality is reassuringly sturdy. The pleated material holds up well under water pressure and regular cleaning. Each panel measures 9 x 8 x 2.1 inches and weighs just over a pound, making them lightweight yet durable. The white color blends inconspicuously into most pool cleaner baskets. Compatibility is extensive, covering over 25 Dolphin and Maytronics models, which adds significant value for households with multiple cleaners or future upgrades.
One potential drawback is that the ultra-fine mesh may clog faster than coarser filters, especially in heavily debris-laden pools. This means more frequent cleaning sessions, but the ease of rinsing offsets this inconvenience. Additionally, while compatibility is broad, it is not universal, so buyers should verify their specific model before ordering. The initial fit on some cleaner baskets might feel snug, but this ensures a secure seal.
Overall, the Henkgo ultra-fine filter panels offer an excellent balance of performance, durability, and affordability. They deliver professional-grade filtration at a fraction of the OEM cost. For Dolphin pool cleaner owners seeking clearer water and less maintenance, these filters are a smart investment. The simple installation and reusable design make them a practical choice for any pool season.
Pros
- Designed to replace Maytronics 9991432-R4 for many Dolphin robotic cleaner models
- Ultra fine pleated media traps both small particles and larger debris effectively
- Reinforced ABS frame keeps the filter stable during operation
- 4 pack provides good value and a longer interval before you need to reorder
- Simple maintenance with periodic rinsing every 4 to 6 weeks
Cons
- Not compatible with many Dolphin models such as Nautilus CC, M600, S200, Triton PS, and others, so check fit carefully before buying
- Aftermarket part is not an original Maytronics product, which may matter to some buyers
- No customer reviews are available yet, so long-term real-world performance is less proven
The Funmit M400 Ultra Fine Cartridge Filter is a 4 pack replacement designed for the Dolphin Nautilus CC Plus and a wide range of compatible robotic pool cleaners. It replaces Maytronics part 9991432-R4, making it a practical option for pool owners who want dependable filtration without the premium price of the OEM part.
The standout feature is the ultra fine pleated filter paper, which captures sand, leaves, hair, and other debris while maximizing surface area. The heavy duty ABS plastic frame keeps the pleats stable during operation and prevents the filter from deforming under water flow, so the cleaner maintains strong suction and consistent performance.
Maintenance is straightforward: rinsing the filter every 4 to 6 weeks is enough to keep it working well, and with proper care each filter can last 2 to 3 years. The 4 pack is especially convenient for owners who clean frequently or have a large pool, because there is always a fresh filter on hand.
The main drawback is compatibility. This filter does not fit several popular Dolphin models, including Nautilus CC, M600, S200, Triton PS, and others, so it is essential to verify your pool cleaner model before purchasing. As an aftermarket part, it also does not carry the original manufacturer branding, though the build quality is solid for the price.
Overall, the Funmit M400 filter replacement offers strong filtration, durable construction, and good value for owners of compatible Dolphin robotic cleaners. If you confirm the fit first, this 4 pack is a smart, budget friendly way to keep your pool clear all season.
Color: White
Dimensions: 10.5 x 6.375 x 10.5 inches
Package includes: 4 cartridge filters
Replaces Maytronics part 9991432-R4
Compatible with Dolphin Nautilus CC Plus, M400, M500, M200, M4, M5, Wave 65, Wave 90, C3, C4, Oasis Z5i, Aquarius XL, Liberty, Odyssey, Sigma, Triton Plus (old)
Buying Guide: What to Look for in Dolphin Aftermarket Replacement Filters
Compatibility with Your Dolphin Model
Not all filters fit every Dolphin robot. Some models use a basket-style ultra-fine filter, while others use individual pleated panels. Before buying, match the part number (like 9991432-R4 or 9991467-R4) to your cleaner’s model list. Many aftermarket brands list compatible models in their description. Double-check that your specific Dolphin version is included, especially if you have an older Active 10 or S50 that may need a small plastic piece removed for proper fit.
Filtration Efficiency: Ultra-Fine vs. Fine vs. Spring
Ultra-fine pleated filters trap the smallest particles, sand, silt, algae, leaving your pool water crystal clear. Fine mesh filters catch larger debris like leaves and twigs. Spring filters (coarse screen) are best for the first few cleanings of a heavily dirty pool, as they prevent clogging. Many owners use a combination: spring filters for initial heavy debris, then switch to ultra-fine for ongoing clarity. Our review of ultra-fine filters explains the differences in more detail.
Build Quality and Durability
Aftermarket filters should have a sturdy ABS plastic frame and well-bonded filter media. Cheaper frames can warp under water pressure, reducing fit and filtration. Look for reinforced edges and tight pleats that hold their shape. Brands like ULTICOR and Gearwiz use high-quality microfiltration technology that lasts through multiple seasons with proper care.
Ease of Cleaning and Maintenance
All filters need periodic rinsing. The best designs pop out easily and clean quickly with a garden hose. Some baskets have numbered panels that guide you during replacement. Rinse every 4 to 6 weeks for optimal performance. If you prefer a basket-style filter, check our top picks for fine filter baskets for models that simplify the process.
Final Thoughts
After reviewing eight Dolphin aftermarket replacement filters, our top recommendation for most pool owners is the Ulticor Ultra Fine Filter Basket Compatible for its exceptional filtration and broad compatibility with popular Dolphin models like the S50, Active 10, and Nautilus CC. If you need a more affordable panel-style solution for newer robots like the Active 20 or S200, the Replace Part#9991467-R4 Ultra-Fine Filter Panels by Henkgo offers great value and reliable performance. Whichever you choose, keeping a clean filter in your Dolphin will extend its life and keep your pool inviting all season long.
Related Guides
- Best Pool Robot Replacement Brush for Algae in 2026
- Replacements for Sparkling Water in 2026
- WYBOT Replacement Brush Review
Frequently Asked Questions
How often should I replace Dolphin aftermarket filters? Most filters last 2 to 3 years with regular rinsing every 4 to 6 weeks. If you notice reduced suction or debris escaping into the pool, it is time for a fresh set.
Can I use a spring filter for everyday cleaning? Spring filters are designed for initial heavy debris removal. For ongoing clarity, switch to ultra-fine pleated filters, which trap smaller particles and keep water sparkling.
Are aftermarket filters as good as OEM Dolphin filters? Yes, many aftermarket brands use premium materials and achieve comparable or better filtration. They are a cost-effective alternative that performs reliably when matched correctly to your model.
Where can I find the right filter for my Dolphin model in 2026? Check the product description for a list of compatible models or refer to our replacement filters category page for updated recommendations.
