Help me choose
A stronger Pool Express option
Dolphin Oasis Z5i and Dolphin S50 are compared feature by feature below. For a stronger Pool Express option, consider Dolphin Cayman. Inground and above-ground pools up to 40 ft that need floor and wall cleaning.
Oasis
Dolphin Oasis Z5i
Inground pools up to 50 ft that need floor, wall and waterline cleaning with app scheduling.
What we recommend instead
Dolphin Cayman
Inground and above-ground pools up to 40 ft that need floor and wall cleaning.
$1,079
Buy Dolphin CaymanDolphin Oasis Z5i or Dolphin S50: our take
Dolphin Oasis Z5i and Dolphin S50 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 S50 is intended for above-ground pools. Dolphin Oasis Z5i is rated for pools up to 50 ft; Dolphin S50 is rated up to 30 ft. Dolphin Oasis Z5i cleans floor, walls, and waterline; Dolphin S50 cleans floor. Dolphin Oasis Z5i lists CleverClean navigation. Dolphin S50 lists 1 active brush.
Filtration and debris
Dolphin Oasis Z5i includes Basket and UltraFilter; Dolphin S50 includes Basket. That gives Dolphin Oasis Z5i the clearer documented edge for fine silt, pollen and sand.
Controls and day-to-day ownership
Dolphin Oasis Z5i provides a weekly timer and smartphone control; Dolphin S50 provides one-touch starts and power-supply controls. Dolphin Oasis Z5i uses continuous corded power, while Dolphin S50 uses a 40 ft corded cable. Dolphin Oasis Z5i is listed at 26.7 lb versus 14 lb for Dolphin S50; that 12.7 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 S50. Dolphin Oasis Z5i and Dolphin S50 each have a specific fit, but neither is the Pool Express pick for this job. Our better alternative is Dolphin Cayman. Inground and above-ground pools up to 40 ft that need floor and wall cleaning.
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 S50 |
|---|---|---|
| Cleans the pool floor | Yes | Yes |
| Climbs and cleans walls | YesEdge | No |
| Scrubs the waterline | YesEdge | No |
| 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 | 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
- 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
Where Dolphin S50 stands out
Dolphin S50 is the better fit for above-ground pools up to 30 ft that need floor cleaning.
- Weighs 14 lb versus 26.7 lb
- Cleans the pool floor
Dolphin Oasis Z5i vs Dolphin S50 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 S50 |
|---|---|---|
| Best fit | Inground pools up to 50 ft that need floor, wall and waterline cleaning with app scheduling. | Above-ground pools up to 30 ft that need floor cleaning. |
| Starting price | See product | $649 |
| Pool type | Inground | Above-ground |
| Maximum pool length | Up to 50 ft | Up to 30 ft |
| Cleaning coverage | Floor, Walls, Waterline | Floor |
| Power | Corded | Corded |
| Filtration | Basket, UltraFilter | Basket |
| Scheduling | Weekly schedule + app | One-touch start |
| App and remote | App control | Power-supply controls |
| Cable | Not listed | 40 ft |
| Robot weight | 26.7 lb | 14 lb |
| Warranty | 3 years | 2 years |
Consider the stronger Pool Express option
Dolphin Oasis Z5i and Dolphin S50 are compared feature by feature below. For a stronger Pool Express option, consider Dolphin Cayman. Inground and above-ground pools up to 40 ft that need floor and wall cleaning.
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