Your robotic pool cleaner works hard all week, but without a quality replacement filter, it cannot trap fine debris or keep the water crystal clear. Whether you own a Dolphin Nautilus CC Plus, Active 20, or an older S50 model, swapping in the right filter basket or cartridge can make a noticeable difference in cleaning performance. This guide highlights seven filters that deliver verified results and are compatible with a wide range of popular pool cleaners.
If you are new to maintaining a robotic cleaner, you might also find our guide on best replacement filters for beginners helpful as a starting point.
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
- Microfiltration prevents clogging and maintains strong suction for thorough cleaning
- Sturdy ABS construction ensures durability even in heavy-duty use
- Wide compatibility saves hassle of finding exact match for various Dolphin models
- Simple maintenance with periodic rinsing; no tools required
- Cost-effective alternative to OEM parts with comparable performance
Cons
- May require more frequent rinsing if the pool is heavily soiled or has fine debris
- Only one basket included; some pool owners may need to purchase additional for larger pools
- Not compatible with all Dolphin models; verify compatibility list before purchase
The Fiitzn Ultra Fine Filtration Basket is a replacement filter designed for a wide range of Dolphin robotic pool cleaners, including models like the S50, Active 15, Echo, Nautilus CC, Encore, E10, E20, Proteus DX3, Solo, and Advantage. This part (9991460-R1) is ideal for pool owners seeking an affordable, high-performance alternative to the original filter. It is especially suited for those who want to improve water clarity by trapping fine particles without sacrificing cleaning efficiency.
The standout feature of this basket is its microfiltration technology, which captures small debris while allowing larger particles to pass through. This design prevents the filter from clogging quickly, ensuring consistent suction and longer cleaning cycles. In real-world use, this means less downtime for rinsing and more effective pool maintenance, even in dirty conditions. The basket maintains strong performance over weeks of use before needing a quick rinse.
Build quality is solid thanks to the ABS plastic frame, which resists cracking and deformation under pressure. The filter layer is securely supported, reducing the risk of tearing during operation. Installation is straightforward: it fits exactly like the original part, so no modifications or adapters are needed. Rinsing every 4-6 weeks keeps it working optimally, and with proper care, the basket can last 2-3 years, offering excellent value.
One potential drawback is that in extremely dirty pools, the filter may need more frequent rinsing to maintain flow. Additionally, the package includes only one basket, so owners of larger pools might need to buy a second. Also, while compatibility is broad, it does not cover every Dolphin model, so double-checking the list is wise. These are minor trade-offs for the price and performance.
Overall, the Fiitzn Ultra Fine Filtration Basket delivers on its promise of efficient fine debris capture and durability. It is a smart upgrade or replacement for Dolphin pool cleaner owners who want to keep their water crystal clear without breaking the bank. The combination of microfiltration, sturdy construction, and broad compatibility makes it a reliable choice for routine pool care.
Dimensions: 9.1 x 7.1 x 5.3 inches
Weight: 1 pound
Material: ABS plastic frame with microfiltration mesh
Compatibility: Dolphin models S50, S100, Active 15, Echo, T15, Proteus DX3, E20, Cayman, Escape, Nautilus CC, Encore, E10, Solo, Advantage
Replaces OEM Part: Maytronics 9991460-R1
Maintenance: Rinse every 4-6 weeks; expected lifespan 2-3 years with proper care
Pros
- Superior filtration from ultra fine pleated material, outperforming standard non-pleated filters.
- Durable ABS frame withstands regular use and chemical exposure without cracking.
- Cost-effective 4-pack reduces per-cartridge cost and frequency of replacement.
- Easy to clean and reuse, extending the life of each filter panel.
- Backed by a 1-year warranty for added confidence.
Cons
- Not compatible with older Nautilus CC, Nautilus (original), or Triton models; verify your robot before ordering.
- Some users may find the initial fit slightly snug in certain robot models, though it settles over time.
- Pleated filters may require more frequent rinsing in heavy-debris pools compared to coarse mesh options.
The SUNRRA Ultra Fine Filters are a versatile replacement option for a wide range of Dolphin robotic pool cleaners, including the Nautilus CC Plus, CC Supreme, M200, M400, M500, and many others. If you own one of these popular Maytronics models and want to improve water clarity, this 4-pack of pleated cartridges is a smart upgrade.
What sets these filters apart is their ultra fine pleated construction. Unlike standard non-pleated cartridges that let fine sediment slip through, the dense pleats trap even tiny particles like algae, pollen, and dust. The result is noticeably clearer pool water and a cleaner floor after each cycle. In real-world use, the filtration performance is excellent, especially for pools that struggle with cloudy water.
The build quality is solid: the frame is made from heavy-duty ABS plastic that resists cracking and tearing, even after repeated rinsing and seasonal storage. SUNRRA claims a lifespan of 2-3 years, which is reasonable if you clean them every 4-6 weeks. The 4-pack also means you have spares on hand, saving you from last-minute replacements.
One important note: these filters are not compatible with the original Nautilus CC, older Nautilus, or Triton series models. Always double-check your robot's model number before purchasing. Also, because the pleats are so fine, they may clog faster in pools with heavy leaf debris; you may need to rinse them more often than coarse mesh filters.
Overall, the SUNRRA Ultra Fine Filters offer excellent value for Dolphin owners who want premium filtration without paying premium prices. The 1-year warranty adds peace of mind, and the 4-pack ensures you're set for multiple seasons. If your robot is compatible, this is a highly recommended upgrade for crystal-clear pool water.
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
Compatibility with Your Dolphin Model
Every filter we reviewed is designed for specific Dolphin robotic pool cleaners. Double-check your cleaner model before purchasing. For instance, the Ulticor Ultra Fine Filter Basket Compatible works with the S50, S100, and many others, while the Gearwiz Ultra Fine Filter Basket Compatible supports newer models like the Active 20 and Explorer E30. Mismatching can lead to poor fit and reduced filtration.
For a broader look at what works with various cleaner types, see our replacement filters category page.
Filtration Technology
Ultra-fine microfiltration technology, found in baskets like the Ulticor and Gearwiz options, captures tiny particles that standard mesh filters miss. Pleated cartridges, such as those from SUNRRA and Funmit, increase surface area for trapping sand, leaves, and hair. Consider the debris type in your pool: ultra-fine baskets excel in fine dust and algae, while pleated cartridges handle larger debris without clogging quickly.
Durability and Maintenance
Most filters use ABS plastic frames that resist cracking and warping. Regular rinsing every four to six weeks extends their useful life, often reaching two to three years. Filters like the Fiitzn Ultra Fine Filtration Basket and the CLLOMAGY 9991467-r4 panels are built to withstand repeated cleaning and heavy use. A durable filter saves you money over time.
Value and Pack Size
Multi-pack options provide excellent value. The Kerneed Spring Filter Cartridges come as a four-pack, covering multiple cleaning cycles before needing replacement. Similarly, the SUNRRA Ultra Fine Filters bundle four pleated panels at a budget-friendly price. If you clean your pool frequently, buying in bulk ensures you always have a spare on hand.
Final Thoughts
Choosing the right replacement filter comes down to matching your Dolphin model and preferred debris type. For owners of newer Active or Explorer models, the Gearwiz Ultra Fine Filter Basket Compatible offers a precise fit and superior microfiltration. If you have an older S50 or Nautilus CC, the Fiitzn Ultra Fine Filtration Basket Compatible is a reliable, durable choice that keeps your pool sparkling clean. Both options have received strong feedback from pool owners who value consistent performance and easy maintenance.
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Frequently Asked Questions
Can I use a different brand filter in my Dolphin cleaner?
Yes, many aftermarket filters from brands like ULTICOR, Gearwiz, and SUNRRA are designed as direct replacements. Always verify the model compatibility list before purchasing to ensure a proper fit.
How often should I replace my robotic pool cleaner filter?
Most filters last two to three years with proper care. Rinse them every four to six weeks to maintain peak performance. If the fabric tears or the frame warps, replace it sooner.
Do ultra-fine filters reduce cleaning time?
Ultra-fine baskets capture more fine debris per pass, which can reduce overall cleaning cycles. However, they may clog faster in very dirty pools, so pairing them with a spring filter for initial heavy cleaning can be beneficial.
Where can I find more filter options for my specific cleaner model?
Check our replacement filters category for guides and recommendations tailored to various Dolphin models and other brands.
