Product guide
Dolphin m400 filter cartridge
Double-check before purchasing
- M400 has multiple hardware revisions — confirm cartridge dimensions with your unit's model number suffix before bulk ordering
Compatibility
The Dolphin M400 filter cartridge is the mesh basket unit that loads into the top-load filter housing. Two cartridges are required per cleaning cycle. Fine and ultra-fine mesh variants are available as direct replacements.
How to Verify Fit
- 'Filter cartridge' and 'filter basket' refer to the same component on the M400 — a rigid plastic-framed mesh unit
- Both cartridge slots must contain matched cartridges — same model, same mesh grade
- Cartridges should seat without force. If forced, they are either the wrong model or incorrectly oriented
Common Mistakes to Avoid
- Confusing 'filter cartridge' terminology with paper cartridges used in sand/DE pool filters — the M400 cartridge is a reusable mesh basket
- Purchasing single cartridges when the M400 requires two per load
- Using worn cartridges because they still look intact — fine mesh degradation (stretch, micro-tears) is not always visible until the pool is dirty after a cycle
When to Replace
Rinse both cartridges after every cycle. Replace as a pair when either is damaged or has lost structural integrity. Annual seasonal replacement is a low-cost best practice.
Buying Tips
OEM Maytronics M400 filter cartridges are widely available. When buying third-party, look for sellers who specifically list M400 compatibility and sell in two-packs. A spare set means no robot downtime.
Where to Buy
Find compatible replacement parts from these retailers:
Frequently Asked Questions
What is a Dolphin M400 filter cartridge?
It is the removable mesh basket inside the top-load panel. 'Cartridge' and 'basket' are used interchangeably by Dolphin owners. It traps debris during cleaning cycles.
How many filter cartridges does the Dolphin M400 need?
Two — one for each slot in the dual-basket filter housing.
Is the M400 filter cartridge reusable?
Yes — it is designed to be cleaned after every cycle and reused until the mesh tears or the frame breaks.
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