Our pick: Dolphin Sigma
Dolphin Sigma is the Pool Express pick in this matchup. Dolphin Sigma includes filtration for sand, pollen and other fine debris. Dolphin Sigma uses 2 active brushes instead of 1.
Proteus
Dolphin Proteus DX5i
Inground pools up to 50 ft that need floor, wall and waterline cleaning.
ProLine
Dolphin Sigma
Inground pools up to 50 ft that need floor, wall and waterline cleaning, with fine debris.
Why Dolphin Sigma is our pick
Dolphin Sigma
Inground pools up to 50 ft that need floor, wall and waterline cleaning, with fine debris.
$2,399
Buy Dolphin SigmaDolphin Proteus DX5i or Dolphin Sigma: our take
Dolphin Proteus DX5i and Dolphin Sigma 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
Both robots are intended for inground pools. Both are rated for pools up to 50 ft. Each cleans floor, walls, and waterline, so coverage alone does not separate them. Dolphin Proteus DX5i lists 1 active brush. Dolphin Sigma lists 2 active brushes, SmartNav 3.0 with gyroscope navigation, and Triple commercial-grade DC motors.
Filtration and debris
Dolphin Proteus DX5i includes Basket; Dolphin Sigma includes Standard filter and NanoFilters. Dolphin Sigma has the clearer documented edge for fine silt, pollen and sand. Dolphin Proteus DX5i also has the better documented path for bulky leaves and larger debris.
Controls and day-to-day ownership
Dolphin Proteus DX5i provides smartphone control; Dolphin Sigma provides a weekly timer, smartphone control, and included remote control. Dolphin Proteus DX5i uses a 60 ft corded cable with an anti-tangle swivel, while Dolphin Sigma uses a 55 ft corded cable with an anti-tangle swivel.
Price, warranty and the decision
Dolphin Proteus DX5i is listed at $1,299 and Dolphin Sigma at $2,399; Dolphin Proteus DX5i is $1,100 less. Dolphin Proteus DX5i lists a 2-year warranty compared with 3 years for Dolphin Sigma. Pool Express pick: Dolphin Sigma. Dolphin Sigma includes filtration for sand, pollen and other fine debris. Dolphin Sigma uses 2 active brushes instead of 1. Choose Dolphin Proteus DX5i when it is the better fit for shoppers prioritizing the lower $1,299 starting price.
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 Proteus DX5i | Dolphin Sigma |
|---|---|---|
| Cleans the pool floor | Yes | Yes |
| Climbs and cleans walls | Yes | Yes |
| Scrubs the waterline | Yes | Yes |
| Fine-debris filter included | No | YesEdge |
| Large-debris filter | YesEdge | No |
| Automatic scheduling | Not listed | Yes |
| Smartphone app | Yes | Yes |
| Anti-tangle swivel | Yes | Yes |
| 3-year warranty | No | YesEdge |
| 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 Proteus DX5i stands out
Dolphin Proteus DX5i is the better fit for shoppers prioritizing the lower $1,299 starting price.
- Includes a large-debris bin or bag for leaves
- Is listed $1,100 lower
Where Dolphin Sigma stands out
Dolphin Sigma is the better fit for inground pools up to 50 ft that need floor, wall and waterline cleaning, with fine debris.
- Includes filtration for sand, pollen and other fine debris
- Uses 2 active brushes instead of 1
- Carries a 3-year warranty instead of 2 years
Dolphin Proteus DX5i vs Dolphin Sigma 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 Proteus DX5i | Dolphin Sigma |
|---|---|---|
| Best fit | Inground pools up to 50 ft that need floor, wall and waterline cleaning. | Inground pools up to 50 ft that need floor, wall and waterline cleaning, with fine debris. |
| Starting price | $1,299 | $2,399 |
| Pool type | Inground | Inground |
| Maximum pool length | Up to 50 ft | Up to 50 ft |
| Cleaning coverage | Floor, Walls, Waterline | Floor, Walls, Waterline |
| Power | Corded | Corded |
| Filtration | Basket | Standard filter, NanoFilters |
| Scheduling | Not listed | Weekly schedule + app |
| App and remote | App control | App + included remote |
| Cable | 60 ft with anti-tangle swivel | 55 ft with anti-tangle swivel |
| Robot weight | Not listed | 24.6 lb |
| Warranty | 2 years | 3 years |
Choose Dolphin Sigma
Dolphin Sigma is the Pool Express pick in this matchup. Dolphin Sigma includes filtration for sand, pollen and other fine debris. Dolphin Sigma uses 2 active brushes instead of 1.
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