Your Dolphin Nautilus pool cleaner has been working hard all season, but you notice it is not picking up debris as effectively. The filters are likely clogged or worn out. Replacing them with the right aftermarket options can restore performance and save money. In this guide, we review the best Dolphin Nautilus replacement filters available on Amazon for 2026, covering ultra-fine and spring filter types. For a broader look at aftermarket choices, check out our guide on dolphin aftermarket replacement filters.
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 for Dolphin Nautilus Replacement Filters
Compatibility with Your Dolphin Model
Not all replacement filters fit every Dolphin model. Most aftermarket filters are designed for the Nautilus CC Plus, M200, M400, M500, and similar models. Always check the product description to ensure your specific cleaner is listed. Some filters explicitly state they are not compatible with older Nautilus CC or Triton PS models. For OEM options, see our Top Dolphin OEM Replacement Filters guide.
Ultra-Fine vs. Spring Filters
Ultra-fine pleated filters capture tiny particles like sand and sediment, keeping your pool water crystal clear. Spring filters use a mesh screen to trap larger debris, making them ideal for initial cleanings after heavy storms or algae blooms. Many users keep both types on hand and rotate them based on pool conditions.
Build Quality and Durability
Look for filters with heavy-duty ABS plastic frames and reinforced pleated fabric. These hold their shape under water flow and resist tearing. Quality aftermarket filters can last two to three years with proper care. Rinse them every four to six weeks to maintain performance. For more on maintenance, read our top dolphin robotic pool cleaner filter baskets article.
Pack Size and Value
Replacement filters come in packs of four or eight. An eight-pack offers better long-term value if you plan to use your pool cleaner frequently. Four-packs are a good starting point to test compatibility and performance before committing to a larger set.
Final Thoughts
Choosing the right Dolphin Nautilus replacement filters comes down to your pool’s specific needs and your cleaner model. For a budget-friendly ultra-fine option that works with many Dolphin models, the Poolzilla Pool Cleaner Ultra-Fine Filters deliver excellent filtration at a low cost. If you prefer a bulk pack for long-term use, the SUNRRA Ultra Fine Filters Compatible with Dolphin eight-pack provides great value and consistent performance. Both are highly rated by users and backed by solid warranties.
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Frequently Asked Questions
How often should I replace Dolphin Nautilus filters?
Most aftermarket filters last two to three years with regular rinsing every four to six weeks. Replace them sooner if you notice tears, warping, or reduced suction. For a deeper look at filter care, see our dolphin pool cleaner filters amazon guide.
Are aftermarket Dolphin filters as good as OEM?
Many aftermarket brands use high-quality materials like heavy-duty ABS plastic and ultra-fine pleated paper that match or exceed OEM standards. They cost less and often come in larger packs. Just ensure compatibility with your specific Dolphin model before purchasing.
What is the difference between ultra-fine and spring filters for Dolphin cleaners?
Ultra-fine filters capture small particles like sand and silt, ideal for maintaining clear water. Spring filters have a mesh screen that traps larger debris such as leaves and twigs, preventing clogging during heavy cleaning. Many users switch between them depending on the season.
Which Dolphin models are compatible with these replacement filters?
Most filters in this guide fit Dolphin Nautilus CC Plus, M200, M400, M500, Supreme M4/M5, Sigma, Wave 60/65/80/90, and others. They are not compatible with older Nautilus CC, Triton PS, or M600 models. Always verify the product list before ordering.
