A stronger Pool Express option
Dolphin M550 and Dolphin Proteus DX3 are compared feature by feature below. For a stronger Pool Express option, consider Dolphin Quantum. Inground pools up to 50 ft that need floor, wall and waterline cleaning, with fine debris.
M-Line
Dolphin M550
Inground pools up to 50 ft that need floor, wall and waterline cleaning with app control, Pick-Up and a caddy.
Proteus
Dolphin Proteus DX3
Inground and above-ground pools up to 33 ft that need floor and wall cleaning.
What we recommend instead
Dolphin Quantum
Inground pools up to 50 ft that need floor, wall and waterline cleaning, with fine debris.
$1,649
Buy Dolphin QuantumDolphin M550 or Dolphin Proteus DX3: our take
Dolphin M550 and Dolphin Proteus DX3 are compared on pool fit, cleaning reach, debris handling, controls and ownership details. The recommendation is based on the job the robot must do—not a simple feature count.
Pool fit and cleaning reach
Dolphin M550 is intended for inground pools, while Dolphin Proteus DX3 is intended for inground and above-ground pools. Dolphin M550 is rated for pools up to 50 ft; Dolphin Proteus DX3 is rated up to 33 ft. Dolphin M550 cleans floor, walls, and waterline; Dolphin Proteus DX3 cleans floor and walls. Dolphin M550 lists 2 active brushes and CleverClean navigation. Dolphin Proteus DX3 lists 1 active brush.
Filtration and debris
Dolphin M550 includes Basket and UltraFilter; Dolphin Proteus DX3 includes Basket. That gives Dolphin M550 the clearer documented edge for fine silt, pollen and sand.
Controls and day-to-day ownership
Dolphin M550 provides a weekly timer and smartphone control; Dolphin Proteus DX3 provides a weekly timer and power-supply controls. Dolphin M550 uses continuous corded power, while Dolphin Proteus DX3 uses a 50 ft corded cable. Dolphin M550 is listed at 22.6 lb versus 14 lb for Dolphin Proteus DX3; that 8.600000000000001 lb difference matters when lifting the robot from the pool.
Price, warranty and the decision
Dolphin M550 is listed at $1,999 and Dolphin Proteus DX3 at $699; Dolphin Proteus DX3 is $1,300 less. Dolphin M550 lists a 3-year warranty compared with 2 years for Dolphin Proteus DX3. Dolphin M550 and Dolphin Proteus DX3 each have a specific fit, but neither is the Pool Express pick for this job. Our better alternative is Dolphin Quantum. Inground pools up to 50 ft that need floor, wall and waterline cleaning, with fine debris.
Feature check: what each robot actually has
A green check means the feature is documented as included. A red X means it is documented as absent. A dash means the source does not make the feature clear.
| Feature | Dolphin M550 | Dolphin Proteus DX3 |
|---|---|---|
| Cleans the pool floor | Yes | Yes |
| Climbs and cleans walls | Yes | Yes |
| Scrubs the waterline | YesEdge | No |
| Fine-debris filter included | YesEdge | No |
| Large-debris filter | Yes | Yes |
| Automatic scheduling | Yes | Yes |
| Smartphone app | YesEdge | No |
| Anti-tangle swivel | Yes | Not listed |
| 3-year warranty | YesEdge | No |
| No recharging between cycles | Yes | Yes |
| Built-in UV-C water treatment | No | No |
Unknown is not treated as “no.” Specifications come from the product pages, current catalog records and manufacturer material collected for this site.
Where Dolphin M550 stands out
Dolphin M550 is the better fit for pools up to 50 ft.
- Cleans the floor, walls and waterline instead of stopping below the tile line
- Includes filtration for sand, pollen and other fine debris
- Uses 2 active brushes instead of 1
- Adds smartphone control
Where Dolphin Proteus DX3 stands out
Dolphin Proteus DX3 is the better fit for shoppers prioritizing the lower $699 starting price.
- Is listed $1,300 lower
- Weighs 14 lb versus 22.6 lb
Dolphin M550 vs Dolphin Proteus DX3 specifications
Use pool fit first. Price and app control do not make up for a robot that cannot cover the length or surfaces you need cleaned.
| Specification | Dolphin M550 | Dolphin Proteus DX3 |
|---|---|---|
| Best fit | Inground pools up to 50 ft that need floor, wall and waterline cleaning with app control, Pick-Up and a caddy. | Inground and above-ground pools up to 33 ft that need floor and wall cleaning. |
| Starting price | $1,999 | $699 |
| Pool type | Inground | Inground, Above-ground |
| Maximum pool length | Up to 50 ft | Up to 33 ft |
| Cleaning coverage | Floor, Walls, Waterline | Floor, Walls |
| Power | Corded | Corded |
| Filtration | Basket, UltraFilter | Basket |
| Scheduling | Weekly schedule + app | Weekly schedule |
| App and remote | App control | Power-supply controls |
| Cable | Not listed | 50 ft |
| Robot weight | 22.6 lb | 14 lb |
| Warranty | 3 years | 2 years |
Consider the stronger Pool Express option
Dolphin M550 and Dolphin Proteus DX3 are compared feature by feature below. For a stronger Pool Express option, consider Dolphin Quantum. Inground pools up to 50 ft that need floor, wall and waterline cleaning, with fine debris.
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