Help me choose
A stronger Pool Express option
Aquabot X2 and Dolphin S400 are compared feature by feature below. For a stronger Pool Express option, consider Clear UV. Inground pools up to 50 ft that need floor, wall and waterline cleaning, with fine debris.
Aquabot
Aquabot X2
Inground and above-ground pools up to 40 ft that need floor cleaning.
S-Line
Dolphin S400
Inground pools up to 50 ft that need floor, wall and waterline cleaning, with fine debris.
What we recommend instead
Clear UV
Inground pools up to 50 ft that need floor, wall and waterline cleaning, with fine debris.
$1,999
Buy Clear UVAquabot X2 or Dolphin S400: our take
Aquabot X2 and Dolphin S400 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
Aquabot X2 is intended for inground and above-ground pools, while Dolphin S400 is intended for inground pools. Aquabot X2 is rated for pools up to 40 ft; Dolphin S400 is rated up to 50 ft. Aquabot X2 cleans floor; Dolphin S400 cleans floor, walls, and waterline. Aquabot X2 lists 1 active brush. Dolphin S400 lists 2 active brushes and CleverClean navigation.
Filtration and debris
Dolphin S400 has documented included filtration—Basket and UltraFilter—while the other model's included media is not fully published. Dolphin S400 has the clearer documented edge for fine silt, pollen and sand. Dolphin S400 has the better documented path for bulky leaves and larger debris.
Controls and day-to-day ownership
Aquabot X2 provides no fully published timer, app or remote specification; Dolphin S400 provides a weekly timer and smartphone control.
Price, warranty and the decision
Aquabot X2 is listed at $497 and Dolphin S400 at $1,799; Aquabot X2 is $1,302 less. Each lists a 2-year manufacturer warranty. Aquabot X2 and Dolphin S400 each have a specific fit, but neither is the Pool Express pick for this job. Our better alternative is Clear UV. 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 | Aquabot X2 | Dolphin S400 |
|---|---|---|
| Cleans the pool floor | Yes | Yes |
| Climbs and cleans walls | No | YesEdge |
| Scrubs the waterline | No | YesEdge |
| Fine-debris filter included | No | YesEdge |
| Large-debris filter | No | YesEdge |
| Automatic scheduling | Not listed | Yes |
| Smartphone app | Not listed | Yes |
| Anti-tangle swivel | Not listed | Yes |
| 3-year warranty | No | No |
| No recharging between cycles | Not listed | 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 Aquabot X2 stands out
Aquabot X2 is the better fit for shoppers prioritizing the lower $497 starting price.
- Is listed $1,302 lower
- Cleans the pool floor
Where Dolphin S400 stands out
Dolphin S400 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
- Includes a large-debris bin or bag for leaves
- Uses 2 active brushes instead of 1
Aquabot X2 vs Dolphin S400 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 | Aquabot X2 | Dolphin S400 |
|---|---|---|
| Best fit | Inground and above-ground pools up to 40 ft that need floor cleaning. | Inground pools up to 50 ft that need floor, wall and waterline cleaning, with fine debris. |
| Starting price | $497 | $1,799 |
| Pool type | Inground, Above-ground | Inground |
| Maximum pool length | Up to 40 ft | Up to 50 ft |
| Cleaning coverage | Floor | Floor, Walls, Waterline |
| Power | Not listed | Corded |
| Filtration | Not listed | Basket, UltraFilter |
| Scheduling | Not listed | Weekly schedule + app |
| App and remote | Not listed | App control |
| Cable | Not listed | 60 ft with anti-tangle swivel |
| Robot weight | Not listed | Not listed |
| Warranty | 2 years | 2 years |
Consider the stronger Pool Express option
Aquabot X2 and Dolphin S400 are compared feature by feature below. For a stronger Pool Express option, consider Clear UV. Inground pools up to 50 ft that need floor, wall and waterline cleaning, with fine debris.
More robotic pool cleaner comparisons
Keep comparing without rebuilding the same specification table yourself.
Clear UV vs Clear S
Pool Express pick: Clear UV
Dolphin Quantum vs Clear S
Pool Express pick: Dolphin Quantum
Dolphin Premier vs Dolphin Sigma
Pool Express pick: Dolphin Premier
Dolphin Premier vs Dolphin Quantum
Pool Express pick: Dolphin Quantum
Dolphin Sigma vs Dolphin Quantum
Pool Express pick: Dolphin Quantum
Dolphin Cayman vs Dolphin Escape
Pool Express pick: Dolphin Cayman