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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
    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: Refurbished


Select Condition:

  • Includes all parts and accessories
  • Verified to work properly
  • Fully tested and inspected with Maytronics testing software
  • Full 3 Year Warranty + 30 Day Risk-Free Trial

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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 SigmaRobots.com

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 SigmaRobots.com

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 SigmaRobots.com

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

Questions and Answers

Do you 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?

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

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.

Compare Dolphin Sigma

Want to compare Dolphin Sigma to other robotic pool cleaners? Read in-depth comparisons against all the top pool robots out there today. Can't decide? Live chat with our pool experts here

Read Our Reviews

Learn more about the Dolphin Sigma on our review. Our in-depth pool robot reviews are written by our pool experts and will help you make an informed decision when purchasing a robotic pool cleaner for your pool. Read the Dolphin Sigma Review or browser other top robotic pool cleaner reviews.

Read Customer Reviews

Overall Rating: 4.8

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

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 2023.