Help me choose
A stronger Pool Express option
Dolphin T55i and Niya Sonar 30 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.
T-Line
Dolphin T55i
Inground pools up to 50 ft that need floor, wall and waterline cleaning, with fine debris.
Niya Sonar
Niya Sonar 30
Inground and above-ground pools up to 33 ft that need floor, wall and waterline cleaning without a cord.
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 T55i or Niya Sonar 30: our take
Dolphin T55i and Niya Sonar 30 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 T55i is intended for inground pools, while Niya Sonar 30 is intended for inground and above-ground pools. Dolphin T55i is rated for pools up to 50 ft; Niya Sonar 30 is rated up to 33 ft. Each cleans floor, walls, and waterline, so coverage alone does not separate them. Niya Sonar 30's documented cleaning system includes 2 active brushes, Sonar navigation, and Three brushless motors.
Filtration and debris
Dolphin T55i includes Basket and UltraFilter; Niya Sonar 30 includes Basket. That gives Dolphin T55i the clearer documented edge for fine silt, pollen and sand.
Controls and day-to-day ownership
Dolphin T55i provides a weekly timer, smartphone control, and included remote control; Niya Sonar 30 provides one-touch starts and power-supply controls. Dolphin T55i uses a 60 ft corded cable with an anti-tangle swivel, while Niya Sonar 30 uses cordless battery power.
Price, warranty and the decision
Dolphin T55i is listed at $1,699 and Niya Sonar 30 at $379; Niya Sonar 30 is $1,320 less. Dolphin T55i lists a 2-year warranty compared with 1 years for Niya Sonar 30. Dolphin T55i and Niya Sonar 30 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 T55i | Niya Sonar 30 |
|---|---|---|
| Cleans the pool floor | Yes | Yes |
| Climbs and cleans walls | Yes | Yes |
| Scrubs the waterline | Yes | Yes |
| Fine-debris filter included | YesEdge | No |
| Large-debris filter | Yes | Yes |
| Automatic scheduling | YesEdge | No |
| Smartphone app | YesEdge | No |
| Anti-tangle swivel | Yes | Not listed |
| 3-year warranty | No | No |
| No recharging between cycles | YesEdge | No |
| 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 T55i stands out
Dolphin T55i is the better fit for pools up to 50 ft.
- Includes filtration for sand, pollen and other fine debris
- Can start on a weekly schedule without a manual launch before every cycle
- Adds smartphone control
- Carries a 2-year warranty instead of 1 years
Where Niya Sonar 30 stands out
Niya Sonar 30 is the better fit for shoppers prioritizing the lower $379 starting price.
- Is listed $1,320 lower
- Three brushless motors, two brushes
Dolphin T55i vs Niya Sonar 30 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 T55i | Niya Sonar 30 |
|---|---|---|
| Best fit | Inground pools up to 50 ft that need floor, wall and waterline cleaning, with fine debris. | Inground and above-ground pools up to 33 ft that need floor, wall and waterline cleaning without a cord. |
| Starting price | $1,699 | $379 |
| Pool type | Inground | Inground, Above-ground |
| Maximum pool length | Up to 50 ft | Up to 33 ft |
| Cleaning coverage | Floor, Walls, Waterline | Floor, Walls, Waterline |
| Power | Corded | Cordless |
| Filtration | Basket, UltraFilter | Basket |
| Scheduling | Weekly schedule + app | One-touch start |
| App and remote | App + included remote | Power-supply controls |
| Cable | 60 ft with anti-tangle swivel | Cordless |
| Robot weight | Not listed | 19.2 lb |
| Warranty | 2 years | 1 years |
Consider the stronger Pool Express option
Dolphin T55i and Niya Sonar 30 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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