Product guide
Dolphin m400 filter basket
Double-check before purchasing
- M400 has had multiple production revisions — verify your unit's basket dimensions match the replacement specification before ordering in bulk
Compatibility
The Dolphin M400 uses a dual-basket top-load filter system. Both fine-mesh and ultra-fine-mesh cartridge baskets are compatible. The M400 is an in-ground pool robot — its baskets are larger than those used in above-ground E-series models.
How to Verify Fit
- M400 baskets come as a pair — both slots in the filter housing must be filled with matching baskets
- Each basket must latch independently with a firm click — a loose basket is a sign of wrong model or a worn latch tab
- Mesh should be evenly tensioned across both baskets — any sagging or holes will reduce filtration
Common Mistakes to Avoid
- Purchasing single baskets when the M400 requires two — always order a matched pair
- Using above-ground Dolphin models baskets — the above-ground Dolphin models is an above-ground model with a different (smaller) basket that will not fit the M400 housing
- Replacing only the more visibly damaged basket and leaving the other — mismatched basket condition causes uneven suction
When to Replace
Clean both baskets after every cycle. Replace the pair when either shows mesh damage. Annual replacement at pool season start is a practical routine for M400 owners.
Buying Tips
Purchase M400 replacement baskets as a pair. OEM Maytronics options are the most reliable. Third-party alternatives are available — ensure the listing explicitly confirms M400 compatibility and pair quantity.
Where to Buy
Find compatible replacement parts from these retailers:
Frequently Asked Questions
How many filter baskets does the Dolphin M400 use?
Two — a left and right basket housed side by side in the top-load panel.
Are the two M400 filter baskets identical?
Yes — both slots use the same basket. Purchase two of the same type (both fine or both ultra-fine) for correct operation.
What is the capacity of the M400 filter baskets?
The M400's dual-basket system provides good debris capacity for medium to large in-ground pools. Actual capacity depends on pool debris load.
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