Help me choose
A stronger Pool Express option
Dolphin Nautilus EON 100 and Dolphin T55i 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.
EON
Dolphin Nautilus EON 100
Inground and above-ground pools up to 50 ft with steps, benches or tanning ledges that need whole-pool cordless cleaning.
T-Line
Dolphin T55i
Inground pools up to 50 ft that need floor, wall and waterline cleaning, with fine debris.
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 Nautilus EON 100 or Dolphin T55i: our take
Dolphin Nautilus EON 100 and Dolphin T55i 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 Nautilus EON 100 is intended for inground and above-ground pools, while Dolphin T55i is 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 Nautilus EON 100's documented cleaning system includes 2 active brushes and SmartMap navigation.
Filtration and debris
Dolphin Nautilus EON 100 includes Basket; Dolphin T55i includes Basket and UltraFilter. Dolphin T55i has the clearer documented edge for fine silt, pollen and sand.
Controls and day-to-day ownership
Dolphin Nautilus EON 100 provides a weekly timer and smartphone control; Dolphin T55i provides a weekly timer, smartphone control, and included remote control. Dolphin Nautilus EON 100 uses cordless battery power, while Dolphin T55i uses a 60 ft corded cable with an anti-tangle swivel.
Price, warranty and the decision
Dolphin Nautilus EON 100 is listed at $899 and Dolphin T55i at $1,699; Dolphin Nautilus EON 100 is $800 less. Dolphin Nautilus EON 100 lists a 1-year warranty compared with 2 years for Dolphin T55i. Dolphin Nautilus EON 100 and Dolphin T55i 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 Nautilus EON 100 | Dolphin T55i |
|---|---|---|
| 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 | Yes | Yes |
| Automatic scheduling | Yes | Yes |
| Smartphone app | Yes | Yes |
| Anti-tangle swivel | Not listed | Yes |
| 3-year warranty | No | No |
| No recharging between cycles | No | YesEdge |
| 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 Nautilus EON 100 stands out
Dolphin Nautilus EON 100 is the better fit for shoppers prioritizing the lower $899 starting price.
- Is listed $800 lower
- Cleans floor, walls, waterline, steps and 8 in ledges
Where Dolphin T55i stands out
Dolphin T55i 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
- Carries a 2-year warranty instead of 1 years
- Runs from continuous plug-in power without a recharge between cycles
Dolphin Nautilus EON 100 vs Dolphin T55i 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 Nautilus EON 100 | Dolphin T55i |
|---|---|---|
| Best fit | Inground and above-ground pools up to 50 ft with steps, benches or tanning ledges that need whole-pool cordless cleaning. | Inground pools up to 50 ft that need floor, wall and waterline cleaning, with fine debris. |
| Starting price | $899 | $1,699 |
| Pool type | Inground, Above-ground | Inground |
| Maximum pool length | Up to 50 ft | Up to 50 ft |
| Cleaning coverage | Floor, Walls, Waterline | Floor, Walls, Waterline |
| Power | Cordless | Corded |
| Filtration | Basket | Basket, UltraFilter |
| Scheduling | Weekly schedule + app | Weekly schedule + app |
| App and remote | App control | App + included remote |
| Cable | Cordless | 60 ft with anti-tangle swivel |
| Robot weight | 22.1 lb | Not listed |
| Warranty | 1 years | 2 years |
Consider the stronger Pool Express option
Dolphin Nautilus EON 100 and Dolphin T55i 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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