Dolphin Sigma Pool Cleaner Review
What's up guys! Ryan here from ActuallyUsed. So, I've been testing the Dolphin Sigma pool cleaner for a few weeks now and... This thing is absolutely insane. If you want the best robotic pool cleaner of the year, this is it. (See how it stacks up against other top models in our best robotic pool cleaners guide.)
If you're on the fence on this cleaner, keep watching. With three commercial-grade motors, NanoFilters, a smartphone app and suction power that's off the charts, it's the top of Dolphin's lineup. And let me show you why it is the best robotic pool cleaner of the year.
Why I'm Impressed
After testing over a dozen pool robots, I have to say - the Sigma is in a league of its own. Most pool cleaners feel just okay, but the Sigma immediately feels like you're dealing with professional-grade pool equipment.
A lot of pool robots on the market right now are cheap, made in China, and cut corners to cut costs. From exposed foam to thin plastic, not all pool robots are built the same.
But the Sigma is different. It's well-made, and built to last. I've been running it consistently for weeks, and it's handling everything like a pro.
When I measured the suction power-and I'll dive deeper into that in a bit-the Sigma had one of the strongest readings I've ever seen. This isn't some number from Dolphin's website; I tested the Sigma myself head-to-head against the top pool robots out there, and it absolutely crushed the competition.
Filtration
The top-loading NanoFilter system is honestly my favorite feature of the Sigma. Most pool robots force you to flip the entire unit over just to get to the filters-but with the Sigma, everything is easily accessible right from the top. It sounds simple, but this little design change makes a huge difference.
You literally just pop open the top, lift the cartridges straight out, and you're good to go. No messy dripping water all over your deck, and no awkward fumbling around. You just snap the filters out and rinse them. Seriously, why didn't someone think of this sooner?
The Sigma also offers multiple filter options:
- NanoFilters - perfect for trapping the tiniest particles
- Standard filters - ideal for everyday, general cleaning
This versatility really sets it apart. If you want truly crystal-clear water, the NanoFilters are your go-to because they catch absolutely everything-from algae and fine sand to larger debris like leaves-without missing a beat.
Now, most other pool robots come with just one filter type, usually a mesh basket. But here's what nobody tells you: those mesh baskets aren't nearly as effective. Cartridges, like those on the Sigma, offer superior filtration because they provide a finer mesh and a more rigid structure, ensuring debris doesn't escape back into your pool.
Not only that, but the dual cartridge design has a larger surface area, allowing it to capture more junk and debris.
The amount of junk the Sigma pulls out is honestly pretty shocking. Fine sand, algae, twigs-whatever your pool throws at it, the Sigma handles it all. These cartridges get PACKED with dirt, leaves, and even algae.
AutoStart with Weekly Smart Timer
This is where the Sigma really shines. While other pool cleaners need constant recharging or to be restarted daily, the Sigma has AutoStart with its Weekly Smart Timer.
What does that mean?
The Sigma automatically turns on and cleans daily for you. Just set the schedule through the app or on the unit, and you're good to go. It's super simple.
You don't have to recharge it or constantly babysit. Just rinse the filter at the end of the week. Full pool cleaning automation at its finest!
Corded vs Cordless
Let's talk about why corded beats cordless every time. There's a lot of marketing around cordless pool robots right now. They look clean in ads with no cable. But after testing both extensively, corded models like the Sigma win hands down. Here's why:
CONSISTENT POWER
The main advantage of corded cleaners is consistent power. With cordless models, you deal with battery fade - strong suction at first that gradually weakens. The Sigma maintains full power throughout the entire cleaning cycle with its three commercial-grade motors.
It's similar to your cordless vacuum at home - remember how it starts losing suction as the battery drains? The same happens in pool robots, but underwater where you can't see it.
THE DAILY ROUTINE
This is what became frustrating when I was testing those cordless models that are all over social media. Every day you have to:
- Fish out the robot
- Carry a dripping, heavy unit to an outlet
- Charge it for hours
- Come back out later in the day and throw it back in
That's two trips a day to use a cordless pool cleaner. After a few weeks, this gets tedious.
With the Sigma, I simply set it and forget it for a week at a time. That's 13 fewer trips to the pool per week.
LONGER CLEANING CYCLES
Most cordless robots run for 60-90 minutes before needing a charge. The Sigma runs for 2.5 hours at a time as a standard cycle, but you could run it all day if you want to. No recharging or downtime, which means more thorough cleaning. And that means a cleaner pool.
When I measured suction power, the numbers were clear:
- The Dolphin Sigma: X PSI
- The Aiper Scuba X1: 1.0 PSI
- The Beatbot AquaSense 2: 1.6 PSI
That's a significant difference that shows up in cleaning performance. This is what happens when you don't compromise on power to make something cordless.
Waterline Cleaning
Here's something most pool robots struggle with - the waterline. The Sigma climbs walls like a beast and actually cleans all the way to the waterline. I've watched it work, and it's like watching a professional climber - methodical, powerful, and effective.
The combination of strong suction and smart navigation means it doesn't just climb up and fall back down like cheaper models. It actually scrubs the waterline where all that gunk builds up.
Smart Navigation
The smart navigation is another thing that just makes me smile every time I watch it work. Most pool robots look like they're just bumping around randomly, right? But the Sigma moves with purpose. It's like watching one of those robot vacuum mapping videos, except in your pool.
Some advantages I noticed:
- It doesn't get stuck in corners like cheaper robots
- It creates efficient paths that reduce redundant cleaning
- It navigates around obstacles effectively
It's actually pretty satisfying to watch it methodically clean every inch
The Smartphone App
Unlike the Dolphin Premier, the Sigma comes with a fully functional smartphone app - and it actually works! I've found a lot of pool robot apps are completely useless. Robots like the Beatbot and Aiper lose connection as soon as they hit the water.
But the Sigma's app? It's rock solid. You can:
- Set cleaning schedules remotely
- Choose cleaning modes
- Control the robot manually
- Monitor cleaning progress
This is what a pool robot app should be - functional, reliable, and actually useful.
"What about the cord tangling?" This is the main concern with corded models. The Sigma's anti-tangle swivel cable works great. During weeks of testing, I haven't had any tangling issues.
The cable combined with the swivel allows it to move freely throughout the pool without knotting up. It's a good example of solving a problem through design rather than removing features.
Performance
After several weeks of daily use, the performance has been consistently excellent. The three-motor system makes a noticeable difference - it picks up everything from fine sand to larger debris without hesitation.
Time is money, right? Well, here's my time comparison with other cleaning methods:
- Manual cleaning: 1-2 hours per week
- Cordless robot: 10 minutes daily (70 minutes weekly)
- Dolphin Sigma: 10 minutes once per week
I saved over an hour a week thanks to the Sigma. That's something I've noticed a lot of other reviews don't cover - but it is a huge difference and testament to how easy the Sigma is to actually use and own.
What's the Downside?
No product is perfect. But the Sigma is pretty close.
The Price
At around $1,700, this is definitely an investment. It's the top of the ProLine, which might be hard to justify if you haven't used a premium pool robot before. But after using several cordless models and other robots, the Sigma is top notch. I would 100% choose the Sigma over any other robotic pool cleaner.
The Long-Term Value
When considering the total cost of ownership rather than just the initial price, the Sigma makes even more sense:
- Less time spent on maintenance (40+ hours saved per year)
- Reduced chemical usage due to better filtration
- Lower energy consumption than pressure-side or suction-side cleaners
- Better warranty coverage
Over a 5-year period, the cost difference between this and cheaper models becomes less significant when factoring in replacement costs and time savings.
Is the Dolphin Sigma worth it?
Bottom line: the Dolphin Sigma isn't just hype. It's the best robotic pool cleaner I've tested, period. (Want to see how it compares to other top picks? Check out our best robotic pool cleaners guide.)
After testing it extensively, the Dolphin Sigma sets the benchmark for a robotic pool cleaner. With three commercial-grade motors, smart navigation, a functional app, and practical features like top-loading filters, it makes pool maintenance actually enjoyable.
For pool owners tired of constant vacuuming, brushing, and headaches, this robot delivers what good tech should: not just good specs, but a cleaning performance that makes owning a pool easier.
Listen, I know it's not cheap. But here's the thing - I've tested over a dozen different pool robots, and I can honestly say this one saves me the most time and frustration. And at the end of the day, isn't that what tech should do?
That's my take on the Dolphin Sigma. Want to see how it compares to other top models? Check out our best robotic pool cleaners guide. If you've got any questions about how it compares to other models, drop them in the comments. Thanks for watching and I'll see you next time!