Help me choose
A stronger Pool Express option
Dolphin Oasis Z5i and Dolphin Premium 40 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.
Premium
Dolphin Premium 40
Inground pools up to 50 ft that need floor, wall and waterline cleaning with app scheduling and a caddy.
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 Premium 40: our take
Dolphin Oasis Z5i and Dolphin Premium 40 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
Both robots are 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 Oasis Z5i lists CleverClean navigation. Dolphin Premium 40 lists 2 active brushes and CleverClean navigation.
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
Both models provide a weekly timer and smartphone control. Both use continuous corded power. Dolphin Oasis Z5i is listed at 26.7 lb versus 18.6 lb for Dolphin Premium 40; that 8.099999999999998 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 Premium 40. Dolphin Oasis Z5i and Dolphin Premium 40 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 Premium 40 |
|---|---|---|
| Cleans the pool floor | Yes | Yes |
| Climbs and cleans walls | Yes | Yes |
| Scrubs the waterline | Yes | Yes |
| Fine-debris filter included | Yes | Yes |
| Large-debris filter | Yes | Yes |
| Automatic scheduling | Yes | Yes |
| Smartphone app | Yes | Yes |
| Anti-tangle swivel | Yes | Yes |
| 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 inground pools up to 50 ft that need floor, wall and waterline cleaning with app scheduling.
- Carries a 3-year warranty instead of 2 years
- 2.5-hour cycle, pools up to 50 ft
Where Dolphin Premium 40 stands out
Dolphin Premium 40 is the better fit for inground pools up to 50 ft that need floor, wall and waterline cleaning with app scheduling and a caddy.
- Weighs 18.6 lb versus 26.7 lb
- 2-hour cycle, pools up to 50 ft
Dolphin Oasis Z5i vs Dolphin Premium 40 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 Premium 40 |
|---|---|---|
| Best fit | Inground pools up to 50 ft that need floor, wall and waterline cleaning with app scheduling. | Inground pools up to 50 ft that need floor, wall and waterline cleaning with app scheduling and a caddy. |
| Starting price | See product | $1,629 |
| Pool type | Inground | Inground |
| Maximum pool length | Up to 50 ft | Up to 50 ft |
| Cleaning coverage | Floor, Walls, Waterline | Floor, Walls, Waterline |
| Power | Corded | Corded |
| Filtration | Basket, UltraFilter | Basket, UltraFilter |
| Scheduling | Weekly schedule + app | Weekly schedule + app |
| App and remote | App control | App control |
| Cable | Not listed | Not listed |
| Robot weight | 26.7 lb | 18.6 lb |
| Warranty | 3 years | 2 years |
Consider the stronger Pool Express option
Dolphin Oasis Z5i and Dolphin Premium 40 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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