Help me choose
A stronger Pool Express option
Dolphin Oasis Z5i and Dolphin T25 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.
Oasis
Dolphin Oasis Z5i
Inground pools up to 50 ft that need floor, wall and waterline cleaning with app scheduling.
T-Line
Dolphin T25
Inground and above-ground pools up to 33 ft that need floor and wall 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 Oasis Z5i or Dolphin T25: our take
Dolphin Oasis Z5i and Dolphin T25 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 Oasis Z5i is intended for inground pools, while Dolphin T25 is intended for inground and above-ground pools. Dolphin Oasis Z5i is rated for pools up to 50 ft; Dolphin T25 is rated up to 33 ft. Dolphin Oasis Z5i cleans floor, walls, and waterline; Dolphin T25 cleans floor and walls. Dolphin Oasis Z5i lists CleverClean navigation. Dolphin T25 lists 1 active brush.
Filtration and debris
Both models include Basket and UltraFilter. Both have documented fine-debris media, so basket capacity and ease of cleaning matter more than fine-particle capability.
Controls and day-to-day ownership
Dolphin Oasis Z5i provides a weekly timer and smartphone control; Dolphin T25 provides a weekly timer and power-supply controls. Dolphin Oasis Z5i uses continuous corded power, while Dolphin T25 uses a 50 ft corded cable. Dolphin Oasis Z5i is listed at 26.7 lb versus 15 lb for Dolphin T25; that 11.7 lb difference matters when lifting the robot from the pool.
Price, warranty and the decision
Dolphin Oasis Z5i lists a 3-year warranty compared with 2 years for Dolphin T25. Dolphin Oasis Z5i and Dolphin T25 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 Oasis Z5i | Dolphin T25 |
|---|---|---|
| Cleans the pool floor | Yes | Yes |
| Climbs and cleans walls | Yes | Yes |
| Scrubs the waterline | YesEdge | No |
| Fine-debris filter included | Yes | Yes |
| 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 Oasis Z5i stands out
Dolphin Oasis Z5i is the better fit for pools up to 50 ft.
- Cleans the floor, walls and waterline instead of stopping below the tile line
- Adds smartphone control
- Carries a 3-year warranty instead of 2 years
- Is rated for pools up to 50 ft
Where Dolphin T25 stands out
Dolphin T25 is the better fit for inground and above-ground pools up to 33 ft that need floor and wall cleaning, with fine debris.
- Weighs 15 lb versus 26.7 lb
- Cleans floor and walls
Dolphin Oasis Z5i vs Dolphin T25 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 Oasis Z5i | Dolphin T25 |
|---|---|---|
| Best fit | Inground pools up to 50 ft that need floor, wall and waterline cleaning with app scheduling. | Inground and above-ground pools up to 33 ft that need floor and wall cleaning, with fine debris. |
| Starting price | See product | $849 |
| 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, UltraFilter |
| Scheduling | Weekly schedule + app | Weekly schedule |
| App and remote | App control | Power-supply controls |
| Cable | Not listed | 50 ft |
| Robot weight | 26.7 lb | 15 lb |
| Warranty | 3 years | 2 years |
Consider the stronger Pool Express option
Dolphin Oasis Z5i and Dolphin T25 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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