Free 1-2 Day Shipping. Low Price Guarantee. Easy Returns/Exchanges.

Choose from top models from the top brands.

Free 1-2 Day Shipping. Low Price Guarantee. Easy Returns/Exchanges.

Choose from top models from the top brands.

Free 1-2 Day Shipping. Low Price Guarantee. Easy Returns/Exchanges.

Choose from top models from the top brands.


Professional level pool robot.

NanoFiltration™. Triple Motors. Gryo.

Dolphin Sigma Robotic Pool Cleaner Dolphin Sigma Reviews Dolphin ProLine Robots
  • Dolphin Sigma
    Open Box
    Pro Line Pool Robot
  • Dolphin Sigma Power Supply
  • Dolphin Sigma Waterline Cleaning
  • Dolphin Sigma High Capacity Filters
  • Dolphin Sigma 3 Year Warranty
  • Dolphin Sigma Gyroscope
  • Dolphin Sigma SmartNavigation
  • Dolphin Sigma Dual Filters
  • Dolphin Sigma Quad Scrubbing Brushes
  • Dolphin Sigma Triple Commercial Grade Motors
  • Cleaning Sigma's Filters
  • Dolphin Sigma In Swimming Pool
  • Dolphin Sigma Robotic Pool Cleaner

Dolphin Sigma

Shipping Truck


Risk-Free 30 Day Trial


3 Year Warranty


Price Match Guarantee

Condition: Open-box


Memorial Day Sale!
Use code MEMORIAL25 to save $25 off any order over $500

Accessories You May Need...

Add a Dolphin Caddy for easy storage and transport


Save Even More...

Sigma's Top Features

Waterline Cleaning

The Sigma's advanced Dual Stabilizers, Triple Motors + Gyroscope allow it to clean like never before.

Dolphin Smart Power Supply

Smartphone App

Manually control, schedule, and read advanced stats about each clean right from Sigma's app.

Dolphin Sigma Gyroscope


Advanced gyroscopic sensors allow Sigma to clean deeper than any other pool robot.

Dolphin Anti-Tangle Swivel

Anti-Tangle Swivel

With Sigma's patented no tangle swivel, the robot can travel freely throughout your pool.

Dolphin NanoFilter Cartridges


Clean small particles other robots cannot capture. Sigma includes the fine and NanoFilter™ cartridge sets.

Dolphin Triple Commercial-Grade Motors

Triple Commercial-Grade Motors

Built on the ProLine™, Sigma's three motors are larger and boast the most power of any Dolphin robot.

Frequently Asked Questions

Why is Poolbots the preferred retailer of Dolphin Open Box and Refurbished pool robots?

As a Maytronics Authorized Dealer, we are proud to offer a full warranty on every Open Box and Refurbished robotic pool cleaner! This means that every robot has full coverage, just like a new one. It's an excellent way to save and find the best deal of the top pool robots!

What's the warranty on Dolphin refurbished robotic pool cleaners?

Each robot includes a full manufacturer's warranty from date of your purchase.

What's the difference between Open Box and Refurbished Dolphin pool cleaners?

Open box units have less than 10 hours on their motor! Refurbished robots will have slightly more hours, but less than 30 hours of use. Both Open Box and Refurbished units include a full manufacturer's warranty!

What's the return policy for Open Box pool robots?

Every open box robotic pool cleaner has a full 30 day return policy, just like a new unit!

What's the return policy of Refurbished pool robots?

Every refurbished robotic pool cleaner has a full 30 day return policy, just like a new unit!

Is there a 30 Day Try Me Program for Open Box and Refurbished pool cleaners?

Yes, every Open Box and Refurbished robot sold by us is included in our 30 day Risk-Free Trial program!

Sigma Product Video

Dolphin Sigma Product Video

The New Sigma. Expect More.

Introducing Gyroscope Technology:
The laws of physics. Reinterpreted.

Take whatever preconceived notions you may have about pool robots and throw them out. The all-new Sigma has set a new standard with unparalleled gyroscope technology and a powerful triple motor design. Now WiFi and app enabled.

Learn more at

The Most Advanced Filters Ever.

Our most advanced filters yet. The Dolphin Sigma includes NanoFilters™ - as they are standard on all ProLine™ pool robots. These filters capture more than the standard filters on other robotic pool cleaners and are found only on the most powerful robots in the Dolphin product range.

Under the lens of a powerful microscope, the Nanofilter's micro-pore spun-bonded polyester fabric reveals a captivating tapestry of intersecting fibers. This intricate mesh allows water to flow freely while effectively trapping minuscule particles. With its deep pleats and impressive gunk-trapping capabilities, the Nanofilter stands out from the crowd. Furthermore, its pleated design offers a significant advantage—a larger surface area for capturing a greater volume of waterborne impurities, all while maintaining optimal water flow.

Learn more about NanoFilters™

Dolphin Sigma Gyroscope Technology

Commercial Grade.
Prosumer Price.

So what exactly makes the Dolphin Sigma the most progressive pool cleaner in the world? It’s rather simple. The ProLine™'s Sigma provides visionary mobility, inspiring design and a whole new focus on sustainability. The result is a technologically superior robotic pool cleaner. The absolute best warranty available and legendary Dolphin pool cleaner performance are standard. Discover new groundbreaking features that represent the current state of pool cleaner technology.

The New Flagship of Dolphin Pool Cleaners

It’s the best Dolphin pool robot ever. It’s easy to see why the new Dolphin Sigma is the answer to the changing demands of pool owners everywhere as it redefines performance in a pool robot. With groundbreaking gyroscope technology, commercial grade motors, and a level of efficiency never seen before, the future has already begun. The newest Dolphin ProLine™ robot features not one, not two but three highly efficient, commercial grade DC motors for the most powerful suction and navigation ever in a robot.

Learn more at

Dolphin Sigma Robotic Pool Cleaner

myDolphin Plus App

More Features. More Power.

myDolphin Plus App

Triple High RPM DC Motors

Our Most Powerful Robot Yet.
Triple Commercial-Grade Motors.

Famous for a high ratio of torque to inertia, the DC motor can provide up to five time it's rated torque without stalling. The Sigma Dolphin pool cleaner utilizes not one, not two, but three onboad DC motors. The revolutionary 24 volt DC motors require 87% less energy than the AC motors that power old fashioned pool cleaners. Efficiency demands power. That was the principle then. And it still stands today. There was an opportunity to get more from less. To optimize the work input to work output. Enter the era of gyroscope enabled robotic pool cleaners.

Learn more at

Superior Surface, Wall and Waterline Cleaning

In a radical departure from ordinary cleaners, the Sigma pool cleaner was designed to clean all pool surfaces including the tile and waterline with pinpoint precision. For the first time ever, a consumer robot is equipped with an advanced Gyroscope to deliver precise control and positioning of the robot. While other cleaners fall from the wall, the all-new gyroscope and triple 3,000 RPM DC motor allows Sigma to remain firmly planted against the wall all the way to the top. Sigma Dolphin pool cleaners reaches every square inch of the pool as high speed spinning brushes handle difficult colonies of bacteria, algae, and biofilm. Sigma reaches deep inside pool corners, scrubs, and vacuums so you don't have to.

Dolphin Sigma Waterline Cleaning
Sigma Waterline Cleaning

Designed from Scratch.
Pushed to the Limit.

Yet again, everything comes back into play. It’s about a new benchmark. We are always looking forward. Not sideways, never back. We started from scratch. And we gave everything we got to make the newest Dolphin even better. Our goal was simple. To create the next Dolphin that can do more, deliver more and consume less power than ever before. The Sigma represents the future of the Dolphin brand. A fascinating future that shows what’s possible. Its design is completely new, but like that of every Dolphin that came before, it’s based on years of research and engineering. The all-new Sigma takes its place at the top of the Dolphin line and in the top echelon of its class.

Obliterate Stubborn Dirt & Contaminants

There are few pool cleaners that are capable of cleaning your pool in a truly satisfying way. It started with a vision. A vision to completely reimagine what we expect from a robotic pool cleaner. Traditional cleaners have no brushes that contact the pool surface. We gave Sigma not one, not two, but four powerful brushes. Engineers gave Sigma dual spinning brushes that power scrub the pool surface and a third center CleanSweep™ brush that rapidly oscillates back and forth to dislodge stubborn contaminants. Together, the triple brush systems provides exceptional agitation and brushing performance.

Powerclean Dual Brushes
Dolphin Sigma Standard Filter

Capture Any Debris.
Dual Oversized NanoFilters™

In addition to vacuuming loose debris, the new Sigma really shines when it comes to difficult to remove contaminants like algae, bacteria, and biofilm that’s firmly attached to the wall of most pools. There are 21,000 known varieties of algae. Chances are, you’ve dealt with at least a few of them. Resistant to chlorine, biofilm is self-perpetuating and very difficult to remove. Traditional pool cleaners only pick up loose contaminants, leaving stubborn contaminants stuck to the pool wall. But the Sigma attacks stubborn contaminants at their core, thanks to its Dual NanoFilters™. Biofilms in swimming pools can and often do lead to cloudy water, algae blooms, scale build-up, and even corrosion.

Try Risk-Free for 30 Days

Buy with Confidence

Try any robot in your pool risk-free for 30 days. We believe a pool robot is an investment, and we know you'll love it. Which is why we have a 30 Day Free Trial. If you don't love it, simply return the robot. Unlike the other guys, we never charge a restocking fee or any other fees - meaning no restocking fee ever.

Here at Poolbots, we carry only the top models for the top brands. All of our pool robots are backed by a full manufacturer's warranty - not prorated or limited to cycles like other pool robots.

Sigma Accessories

Dolphin Universal Caddy

Easily transport your Dolphin Sigma with the Dolphin Universal Caddy. Fits any Dolphin Robotic Pool Cleaner.

Dolphin Sigma Specifications

Waterline Cleaning Yes
Wall Climbing Yes
Dual Stabilizer Yes
Number of Motors 3
Gallons Filtered Per Hour 4500 GPH
Filter Types Ultra-fine and Standard Filter Cartridge sets
Pool Coverage Floor, Walls, Waterline
Pool Types In Ground
Pool Size 50 ft
Pool Shapes Rectangle, Oval, or Freeform
Pool Surfaces Concrete, Plaster, Gunite, Pebble, Tile, Vinyl Liner, Fiberglass
Cable Length 60 ft
Anti-Tangle Swivel Yes
Obstacle Avoidance Steps, Ladder, Drain Cover, Ledges, Pop-Ups
Warranty 3 Years
Brand Dolphin
Manufacturer Maytronics
Part Number 99991036-SPLI
Microsite Visit Microsite

Dolphin Sigma Manual & Guides

Read Customer Reviews

Overall Rating: 4.4

Brian Bertha - 5 Stars

I have the sigma (previously owned s300i) cleans great better than my old one. Was getting stuck on drains I called factory. I had to ship it to them (they paid for the return) the added a middle brush fixed the problem Shipping wasnt cheap but it was worth it

Beverly R - 5 Stars

We have been unground pool owners for years so when I found this pool cleaner I was hopeful. This is the BEST pool cleaner we have ever had. So easy to use. There pool is so clean! You don't need to attach to the pool filter in any way. We just drop it in the pool and push start. I would highly recommend this cleaner. It's worth every penny

mike scott - 5 Stars


Eric F - 5 Stars

Bought this last season, and am extremely impressed. Came from a Tigershark, which did an OK job, but would get stuck too often in my pool. The Sigma has yet to get stuck once all last season and after about 10 uses this season. Powerful pumps, ripples the top of the water from 10 feet deep. Quick cleaning. Bluetooth is hard to use for spot cleaning, I just don't bother with it. It cleans my 20x40 foot pool in about 2.5 hours, no need to spot clean after. If it lasts another 2 seasons, I will consider it one of my best purchases for pool cleaning. Have not felt the need to manually vaccuum since I bought it. Highly recommend.

Glenn - 5 Stars

Great. Does not get hung up... Does a great job.

Write a Review

Questions and Answers

Does Poolbots charge any restocking fees in your 30 Day Free Trial?

No, we never charge a restocking fee ever! We know a robotic pool cleaner is a big investment, which is why we offer Free 30-Day Trials on all robotic pool cleaners!

How long is the Dolphin Sigma's warranty?

As a proud Authorized Dealer for Dolphin, the Dolphin Sigma includes a full 3 year warranty from date of purchase.

Does Dolphin Sigma need a booster pump to work?

No! The Dolphin Sigma is plug and play! All you need to do is unbox the unit and plug it into an outlet. No setup or assembly required!

My Dolphin Sigma gets stuck on drains, how can I fix this?

With a main drain clip on, you can successfully avoid the robot getting stuck on your drain.

Does the Dolphin Sigma work with saltwater pools?

Yes. The Dolphin Sigma works with all types of pools, including freshwater and saltwater.

What types of pools does the Dolphin Sigma work with?

The Dolphin Sigma is compatible with the following types of pools: In-ground pools, above-ground pools, gunite pools, tile pools, fiberglass pools, and viny pools of all shapes and sizes. If you have any questions or wonder if this is the right robot for you, contact us or view our Pool Robot Guide.

Does the Dolphin Sigma have WiFi/Bluetooth?

Yes, the Dolphin Sigma has wifi and bluetooth that allows you to connect and control the robot from the app.

Does the Dolphin Sigma have an app?

Yes, the Dolphin Sigma has an app to control the robot.

How long does Nautilus CC Plus run for?

The Dolphin Sigma cleans for 2.5 hours. You can set the robot to run daily via its included programmable timer.

How much does Dolphin Sigma weigh?

The Dolphin Sigma weighs 24.63 lb.

How does Dolphin Sigma work?

The Dolphin Sigma works as an automatic robotic pool cleaner. It will vacuum, scrub, and automate your pool cleaning. With a plug and play design, all you need is an outlet to plug it into and you’re good to go. No booster pump or assembly needed.

Does Dolphin Sigma pick up leaves?

The Dolphin Sigma is great at cleaning and picking up leaves. With a larger filter and strong flowrate, the Sigma can vacuum leaves with ease.

Does Dolphin Sigma pick up sand, algae, or small debris?

The Dolphin Sigma cannot perform as well as robots with NanoFiltration. As the mesh filters on Dolphin Sigma cannot capture small particles like the newer Gen-2 NanoFilters. See all robots with NanoFiltration here.

Does Dolphin Sigma come with NanoFilters?

The Dolphin Sigma does not have NanoFilters. See all robots with NanoFilters here.

Does Dolphin Sigma clean waterline?

Yes, the Dolphin Sigma cleans the waterline.

Does Dolphin Sigma climb walls?

Yes, the Dolphin Sigma cleans your entire pool - including the floor, walls, and waterline.

Can the Dolphin Sigma be plugged into an extension cord?

Yes it can!

I can power my Dolphin Sigma on but it does not move

If your Dolphin powers on but does not move, try checking the tracks for any debris or obstructions. Also, check the drive motor and impeller for any damage or wear. If you are still having issues, contact Maytronics customer support for further assistance.

My Dolphin Sigma's power supply does not turn on when I press the power button

If your Dolphin's power supply is not turning on, check to make sure it is properly plugged in and that the outlet it is plugged into is working. If the power supply is still not turning on, contact Maytronics customer support for further assistance.

My Dolphin Sigma is not cleaning the pool properly

If your Dolphin Sigma is not cleaning the pool properly, try checking the filter bag for any debris or blockages. Also, check the brushes and tracks for any damage or wear. If you are still having issues, contact Maytronics customer support for further assistance.

What are the handles and the floats on my Dolphin for?

The handles on your Dolphin are for lifting and carrying the unit, while the floats are designed to help your Dolphin navigate around the pool and maintain proper buoyancy.

There seems to be something stuck in my Dolphin Sigma's' tracks – how can I get it out?

To remove any debris or obstructions from your Dolphin's tracks, turn off the power supply and carefully remove the tracks from the unit. Use a soft brush or cloth to clean the tracks and remove any debris. Once clean, reattach the tracks to the unit.

The cord is connected to the robot's power unit, but the power unit LED indication is off.

If the power unit LED indication is off even when the charger is connected, please try the following steps: 1) Unplug the power supply from the outlet and wait for 10 seconds. 2) Plug the power supply back in and check if the LED indication turns on. 3) If the LED indication still does not turn on, contact Maytronics customer support for further assistance.

Why should I register my robot?

Registering your Dolphin robotic pool cleaner allows you to receive important product updates and notifications, as well as access to exclusive content and promotions.

What's Next?

Learn more about Nanofilters™, MaxBin™, and so much more to find which pool robot is right for you. Use our Pool Robot Selector to enter your pool type and find an exact match for your swimming pool's needs or read the Best Dolphin Pool Cleaner for 2024.