Product guide
Dolphin m400 replacement filter
Double-check before purchasing
- M400 production has multiple hardware revisions; confirm basket dimensions match your unit before purchasing a large quantity
Compatibility
Replacement filters for the Dolphin M400 are available as OEM Maytronics cartridges and from third-party compatible suppliers. The M400 uses two filter baskets (fine or ultra-fine mesh) loaded into the top-load panel.
How to Verify Fit
- Replacement baskets should be labelled for M400 or in-ground Dolphin models — not for above-ground E-series
- Both replacement baskets must be the same size and mesh grade to ensure even suction across both chambers
- New baskets should click into place without force — forced fit indicates wrong model
Common Mistakes to Avoid
- Only replacing one of the two baskets — both should be replaced at the same time for consistent performance
- Purchasing E10 or other above-ground model baskets by mistake — they are physically smaller and will not fit correctly
- Waiting until suction fails noticeably before replacing — proactive seasonal replacement is better for pool cleanliness
When to Replace
Clean after every cycle. Replace both filter baskets at the same time — typically once per swimming season for regular use, or when mesh damage is found.
Buying Tips
Buying a two-pack (one pair) of M400 replacement filter baskets ensures you have a matched spare set ready. OEM Maytronics filters are the most reliable. Reputable third-party options offer savings — always verify explicit M400 compatibility.
Where to Buy
Find compatible replacement parts from these retailers:
Frequently Asked Questions
How do I replace the filter in my Dolphin M400?
Open the top-load access panel. Remove both existing baskets by lifting them out. Insert the new baskets with handles facing up and aligned with the guide slots. Close the lid until it clicks.
Do M400 replacement filters come in different grades?
Yes — standard fine-mesh and ultra-fine-mesh variants are both available for the M400. Choose based on your pool's debris type.
How do I dispose of old Dolphin filter baskets?
They are plastic — check your local recycling guidelines for plastic mesh products.
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