MyDolphin app on your smartphone, where you can control it for a manual spot clean.

Anti-Tangle Swivel
This thing is a game-changer. It keeps the 60-foot cord from tangling into an impossible heap. Without it, you’d probably regret ever owning a pool.

Three-Year Warranty
Maytronics, the manufacturer of the Oasis Z5i, promises a limited three-year warranty if you encounter any mishaps.

Energy Efficient
Despite its size and power, the Oasis Z5i is remarkably energy efficient. It costs an average of five cents an hour to run, and it consumes 90% less power than traditional suction cleaners.

The Oasis Z5i in Action
Nimble Underwater
It was impressive to watch the dynamic dual drive motors at work. The Oasis Z5i can spin around in the same spot, shimmy into tight corners, and climb effortlessly to the pool’s waterline.

For being so big (24 pounds), the Oasis Z5i moves very gracefully. Especially as it climbed walls, it only faltered once when it hit a slippery patch of algae. However, it quickly rerouted and climbed the same strip of wall again. Even when it came upon a deep underwater cove beneath a built-in rock waterfall, it managed to climb up the curve and above the waterline, which we’ve never seen a robotic pool cleaner do before. It even tried to climb far enough above the waterline to reach the top of the adjoining hot tub, but it fell back before it could dive in.

Where It Faltered
The Oasis Z5i managed to climb the bottom two steps of the underwater stairs, but it couldn’t climb any higher. We weren’t surprised by that, as few robotic pool cleaners consistently and efficiently clean underwater steps.

It also struggled to scrub an underwater bench that lies next to a built-in underwater table. It was a very narrow fit, anyway, so that’s an area that would have to be manually brushed.

Cleaning Power
The two active spinning brushes worked overtime during the Oasis Z5i’s two-hour cleaning job. We saw them sweep up the larger, more visible debris from the bottom of the pool, and it swept away smaller particles as well (as evidenced in the filter findings).

Improving Water’s Clarity
We used the fine filter cartridges initially, and they did a great job of picking up medium-large debris. We wanted to see how the Oasis Z5i cleaned with the ultra-fine filters in place, so we sent it back to work for a short cleaning job (one hour).

Using the ultra-fine filters made a huge difference in the pool’s water clarity. It was more capable of capturing the smaller particles that were clouding the water, leaving it brighter and more sparkling-clean than before.

Filtration Observations
The top-loading cartridges aren’t as easy to remove and clean as some of Dolphin’s top-loading baskets, but they’re still far better than filter bags. Yuck.

The oversized cartridges snapped apart easily to reveal an impressive amount of debris. On the first cleaning job with the fine filter, we found more large debris than we expected – small twigs, leaves, acorns, and bits of flora. When we opened the ultra-fine filter cartridge, we saw all of the gunk that had been clouding the water. It was trapped in the fine folds of the filter itself, and there was a substantial muddy residue in the cartridge.

Usability
Technology
Figuring out the multi-function power supply is pretty straightforward. The Oasis Z5i doesn’t come with an in-depth user guide, but you can figure out how to start a cleaning job, select a mode, and schedule a weekly timer easily.

Using the MyDolphin app, on the other hand, isn’t as user friendly. We didn’t have trouble connecting the Oasis Z5i to the app, but using the manual navigation was frustrating. If being able to manually spot clean is important to you, you can take the time to learn how the cleaner responds to the app. But in the beginning, it’s frustrating because of delayed responses and jerky, unintuitive movements.

Maintenance
The top-loading cartridges are very easy to clean. Simply snap them apart, dump the debris, and rinse clean. Just be sure you don’t leave anything to dry out while dirty.

The Oasis Z5i weighs 24 pounds. Although that weight doesn’t hinder it underwater, it can be a strain on your back once it’s out of the water. Unfortunately, it doesn’t include a caddy with purchase. That’s something we’d expect and hope for at this price range. Nonetheless, it’s a worthwhile investment, especially since the caddy elevates the sponge rollers and brush bristles from being squished on the ground.

Dolphin’s patented anti-tangle swivel is once again a superstar. It prevents the cord from developing those hard-to-remove knots, so you can breathe easy knowing you won’t have to stretch the cord out after each and every cleaning.

Pros
Dynamic Dual Drive
The dual drive motor gives the Oasis Z5i its commercial-grade power. It moves steadily and seamlessly underwater, completely unbothered by protruding drains, steep drops, or climbing walls. Watch it work and move in every direction like it isn’t hindered by the laws of physics and you’ll be impressed, too.

Excellent Coverage
Except for the underwater steps and bench, the Oasis Z5i covered the entirety of our pool’s surfaces. It even scrubbed the waterlines consistently and efficiently.

Powerful Climbing
The thick tracks on the treads of the Oasis Z5i combined with its dual motors make it an excellent climber. Even from the deepest points of the pool, it powered up to the waterline with each pass-through.

Fantastic Filtration
Having the option to use a fine or ultra-fine filter cartridge makes a world of difference. For larger debris cleanups, use the fine filter. To really capture the nitty gritty, use the ultra-fine filter and watch your water clarity improve. Either way, you’ll find more debris in the cartridges than you’d expect.

Three-Year Warranty
It’s hard to find a warranty better than this. Dolphin covers plastic parts, the power supply, cable, and motor for 36 months. So, in the rare event something does go wrong or needs replacing, you’re covered.

Cons
Caddy Not Included
At this price range, we wish the caddy were included. Especially because the Oasis Z5i weighs a whopping 24 pounds. If you do decide to purchase this model, we suggest springing for the caddy on top of the regular costs. It makes transportation and storage that much easier.

Bluetooth Navigation Isn’t Perfect
The Oasis Z5i functions perfectly without using the Bluetooth navigation, but it is a chunk of what you’re paying for with this model. Many pool owners will opt to ignore it completely, as the robot lags in response to commands and takes forever to do a simple “spot” clean. Honestly, it might be easier to just toss it in the pool and set it for a quick one-hour cleaning job.

Cleans Almost Everywhere
To be fair, only a handful of robotic pool cleaners are capable of cleaning the entire pool. And they cost a lot more than the Oasis Z5i. That being said, you’ll still need to observe where this model can and cannot reach so you can be sure to manually brush those spots. Keep an eye on steps, tanning ledges, benches, etc.

Ultimately…
If you value power, efficiency, and durability, the Oasis Z5i is for you.

It blends the best of both brains and brawn. It is powerful enough to tackle pools up to 50 feet long, climb to waterlines, and scrub the stuck-on grime out of surfaces with double spinning brushes. Its intelligent features are the perfect addition to an already solid machine, sensing where it has and hasn’t been, creating efficient cleaning routes, and operating off of a weekly timer.

The Oasis Z5i is excellent for larger pools that need moderate cleaning regularly. It’s an underwater tank that will surprise you with its dexterity and durability. Even with the spotty Bluetooth navigation, it’s still a solid robotic pool cleaner that you won’t regret investing in