In-Ground Dolphin Sigma Pool Cleaner

Published on March 16th, 2019 | by Roger Corbinetti


Dolphin Sigma Robotic Pool Cleaner: My In-Depth Review

Dolphin Sigma Robotic Pool Cleaner: My In-Depth Review Roger Corbinetti


Wall Cleaning
Energy Efficiency
Floor Cleaning

Summary: The Dolphin Sigma is a full-featured premium workhorse for larger in-ground pools. Not the best at cleaning stairs, but otherwise this bot is one of the very best robotic pool cleaners selling today.


Perfect for in-ground pools without stairs.

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Price:  on Amazon

  • For in-ground pools with any type of surface.
  • Smart mapping and gyroscope-enabled navigation.
  • Three (3) high-performance energy-efficient DC motors.
  • Independent tracks.
  • Dual active scrubbing split brushes.
  • Bluetooth and WiFi control via a smartphone app.
  • Programmable weekly timer.


The Dolphin Sigma is the latest addition to the Dolphin lineup of robotic pool cleaners. And it may very well be the best Dolphin pool cleaner ever manufactured by Maytronics.

The Sigma is designed to clean in-ground pools of all shapes and surfaces. It comes with smarter navigation, more cleaning power and more features than pretty much all other robotic pool cleaners in the market.   The closest models I can think of to compare this with include the Polaris 9550 and the Dolphin Premier.

The Sigma one of the few robotic pool cleaners with Bluetooth connectivity, too. This lets you to control the robot from your smartphone no matter how far back from your home your pool lies.

Of course, this is not the least expensive cleaner. Going for well over $1,000, you’ll have to dig deep for the Dolphin Sigma – but honestly, I think it’s worth it.

That said, it’s not perfect – the Sigma isn’t the best stair cleaner, for example.

Keep reading for my in-depth review of this excellent new robotic pool cleaner from the world’s leading manufacturer of robotic pool cleaners.

If you are looking for something less expensive for your in-ground pool, then read about my other favorites in my inground pool cleaner buying guide.

If you need a pool cleaner for an above-ground pool, the Sigma is not your best choice (it’s kinda overkill).  Read my above-ground cleaner buying guide to find less expensive options.

Dolphin Sigma Video Introduction


Cleaning Ability

Dolphin Sigma’s cleaning ability matches its high price tag. It cleans better, faster and more efficiently than most other robotic pool cleaners thanks to a number of recent innovations.

One of the biggest changes is the use of a triple motor system.  That’s right – three drive motors.

The motors propel the robot around the pool floor and walls effortlessly while powering a high-performance suction system that picks up everything from tiny algae to large chunks of debris.

The independent strong-grip tracks and the integrated gyroscope technology help the Dolphin Sigma robot navigate your pool extremely efficiently. It can turn on the spot, crawl walls and move over slippery surfaces without a problem.

Dual split brushes agitate and remove stubborn algae and dirt from your pool’s surfaces while dual filters ensure that all debris is picked up, both coarse and fine. The top-access cartridges also hold a lot of debris before you need to empty them.

Whether you are cleaning your pool for the first time in months or just doing routine cleaning, the Dolphin Sigma is up to the job.

The Sigma’s cleaning cycle is a bit longer than most at around 2.5 hours, but this allows it to clean more thoroughly. You’ll probably only need to clean your pool 2-3 times a week.

Best Features

1. SmartNav™ 3.0 Scanning and Mapping With Gyroscopic Navigation

Dolphin Sigma Pool Cleaner

Most Dolphin pool cleaners use the SmartNav smart scanning and mapping system.

For the Sigma, Dolphin updated to its latest version which provides even more precise pool scanning for better cleaning.

SmartNav 3.0 maps and remembers your pool’s shape, size and contours and uses this data to calculate the best cleaning pattern.

So instead of wandering randomly like many low-cost pool cleaners, it follows a precise path that covers every square inch of your pool while using as little energy as possible.

SmartNav 3.0 also tells Sigma where it has already cleaned, ensuring it doesn’t waste time and power going over the same areas more than once.

The Dolphin Sigma also comes with a gyroscopic navigation system that gives it better location awareness. It is the first robotic pool cleaner to be equipped with a gyroscope, in fact.

The Sigma’s gyroscope sensors – the same used in planes, some drones and the Mars rover – also improve the robot’s ability to turn and tilt while moving vertically on the wall and crawling along the floor.

2. Triple Motors

Dolphin Sigma Pool Cleaner

Another first in the Dolphin Sigma is the use of three motors.

Most robotic pool cleaners have one motor, and a few premium ones spot two. The Sigma uses three high RPM commercial-grade DC motors.

This makes the Sigma one of the most powerful robotic pool cleaners sold today.

It moves easily and quickly in the pool, rarely if ever gets stuck and has impressive suction power.

But just because the Sigma’s 3 motors are powerful doesn’t mean they are power-hungry.

These 24V DC motors use 87% less energy than traditional AC motors.

Overall, the Sigma robot cleaner uses up to 90% less power compared to suction/pressure side pool cleaners.

3. Independent Rubber Tracks

Dolphin Sigma Pool Cleaner

Similar to other premium robot pool cleaners, the Dolphin Sigma uses tracks rather than wheels. Tracks provide better traction and can tackle walls and obstacles better.

But Sigma’s HyperGripTM tracks are unique, as they operate independently of each other.

This means that one track can turn in one direction while the other turns in the opposite direction. This allows the robot to turn completely around on the spot.

4. Dual Active Scrubbing Brushes

Dolphin Sigma Pool Cleaner

The Dolphin Sigma uses dual high RPM brushes to gouge stubborn dirt and algae off your pool’s surfaces.

The brushes are split, meaning there are 4 brushes in total: two at the front and two at the rear.

5. Dual Filtration

The Sigma comes with two types of filters.

One is for large debris like leaves, twigs and small rocks, and the other is for fine and ultra-fine stuff like algae, sand and dust.

6. Oversized Top-Load Filter Cartridges

Dolphin Sigma Pool Cleaner

Dirt and debris is collected into two extra-large cartridges.

These are top-load style cartridges, so removing them does not require lifting and turning this rather heavy unit over.

7. Programmable Weekly Timer & Bluetooth Control

You don’t have to be home to clean the pool with the Dolphin Sigma. Just select an auto-cleaning schedule from the three options available – daily, 2X a week, 3X a week – and let the robot do its thing.

Just make sure to leave it in the water for it to start cleaning automatically.

The Dolphin Sigma doesn’t come with a remote control – but you don’t need one. You can use your smartphone courtesy of the MyDolphin app which you need to download and install.

The Sigma pool robot also has Bluetooth connectivity, which is really important for homes that have pools set back from their back door where WiFi might be spotty. Once you connect your phone, you use it as a remote control. Note: you need to download the MyDolphin app to use Bluetooth control.


  • Triple motors = one of the most powerful and capable robotic pool cleaners around.
  • Smart mapping / navigation reduces cycle times and saves energy.
  • Easy to use and clean top-access cartridges
  • Bluetooth connectivity (important for pools set away from the home).
  • Oversized cartridges that don’t need to be emptied midway through the cleaning.
  • Dual filters for improved cleaning.
  • No-frustration 360 degree swivel cable.
  • Weekly timer with lots of flexibility.


  • Pricey. But considering all the features you get, I think it’s worth it.
  • Has a bit of trouble cleaning steps.
  • Not a lightweight.


  • Cleaning Cycle: 2.5 hr
  • Dry weight: 22 lbs
  • Dimensions: 23.4 x 19.7 x 14.3 inches
  • Cable Length: 60 feet
  • Suction rate: 75 gallons per minute
  • Plug and Play installation


If you are looking for a capable robotic pool cleaner for your in-ground pool, the Dolphin Sigma is one of my top recommendations. It has pretty much every feature I like to see – top loading dual filters, multiple motors, tangle free cable, great cleaning, stair-cleaning and flexible programmability.

The new Dolphin Sigma will set you back more than most pool cleaners, but it’s probably the best premium cleaner sold on the market today. That, or the Dolphin Premier.


About the Author

I’ve owned a pool for over 20 years. During that time, I have owned and reviewed dozens of pool cleaners, especially robotic pool cleaners. I created RoboticPoolCleanersCompared to help other home owners leverage my experience to select the right pool cleaner, pool heater, pool cover and modern pool appliance for their needs & budget.

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