Dolphin Sigma vs Dolphin Quantum Pro. Two of the strongest pool robots I’ve ever tested. Both under the ProLine badge. And on my gauge, a single tenth of a PSI between them. The Dolphin Sigma pulled 2.0 PSI in my manometer testing. The new Dolphin Quantum Pro pulled 1.9 — same pool, same gauge. They share the same app, the same swivel cable — and a price gap wide enough to make you stop and think.
So which one is better? I’ve run both for weeks, side by side, and today we’re settling it: suction, intake width, app features, warranty, value — and the one job the Quantum Pro does that the Sigma won’t touch. Let’s dive in.
Hey guys, I’m Ryan with ActuallyUsed, where we put the products to the test so you don’t have to. Every robot that comes through here gets weeks in our pool, and every single one gets hooked up to my hydro manometer — the device that measures actual suction pressure right at the intake port. Today, two of the strongest robots I’ve ever measured go head to head.
How I Test — and Why PSI, Not GPH
Quick refresher for the new folks. Manufacturers publish GPH — gallons per hour moving through the pump. I measure PSI at the intake port — how hard the robot pulls when it rolls over sand, silt, and acorns. Both numbers are real; they just answer different questions. And I’m not saying the brands quoting big flow numbers are being dishonest — they’re measuring something different than I am. In my experience, PSI is the number that decides whether your floor actually comes clean. At this point, my logbook covers manometer readings on more than two dozen robots, plus tape-measured intake ports on over 40. That’s the ruler we’re using today.
Meet the Contenders
In one corner: the Dolphin Sigma, the tech flagship of Dolphin’s ProLine. Three commercial-grade motors, gyroscope-fed SmartNav navigation, top-loading NanoFilters, and a 3-year warranty — triple the coverage of most robots I’ve reviewed. Retail sits around $3,000, though you can usually find it on sale for well under that.
In the other corner: the Dolphin Quantum Pro, the 2026 addition to the ProLine and the replacement for the original Quantum — a robot that was one of my favorite value picks for years. It keeps the ProLine DNA, adds a real answer for sun shelves and steps, and comes in at $2,499 MSRP — a meaningful gap below the Sigma. Now, are the Dolphin Quantum and Dolphin Quantum Pro different? No. It is the same unit. Dolphin just updated the sticker it seems so you know you are getting the latest model!
Same badge. Same family. But after weeks with both in my water, they are not the same robot. Round one.
Round 1 — Suction
With the manometer sealed on the intake port, the Sigma pulled exactly 2.0 PSI in my testing. The Quantum Pro peaked at 1.9 — same pool, same gauge, same method.
Context, because numbers mean nothing on their own. Only two robots out of the two-dozen-plus on my leaderboard have ever pulled more than the Sigma — and I’ll stack our contenders against both of them in a minute. No battery-powered robot in my logbook has hit 2.0 — not one, at any price. So these are the third- and fourth-strongest readings I have ever logged, and in my testing, the Quantum Pro out-pulled cordless flagships costing two to three times its price. This is a fight at the top of the mountain.
But is one tenth of a PSI real? Here’s my read, based on my results. Both robots grabbed the obvious debris — leaves, acorns, bugs — without drama. The gap showed up on the fine stuff. On silt and algae dust, the Sigma got to first-pass pickup a little more consistently in my pool. My theory is that the last tenth matters most right at the edge of the port, where a particle either commits or skates by. That’s my opinion from my testing, not a lab certification. But the number is the number, and the eye test agreed with it.
Round one: Sigma.
Round 2 — Intake Path
Suction is half the equation. The other half is how wide a bite the robot takes on every pass — a spec almost nobody publishes, which is exactly why I keep a tape measure next to the manometer.
The Sigma runs two intake ports at five inches each. That’s ten inches of total intake path — the widest I’ve measured on any robot, corded or cordless, out of the 40-plus I’ve put the tape on. The Quantum Pro runs a single center port. It’s a proven layout — most of the industry builds them that way — but it is not ten inches of mouth.
Why does width matter? Coverage math. A wider path means fewer passes to sweep the same floor, and fewer chances for a leaf to skate around the port on a turn. Pair ten inches of intake with 2.0 PSI of pull and, in my experience, you get first-pass pickup — the robot isn’t circling back for debris it missed.
Round two: Sigma.
Round 3 — The App and Smart Features
Both robots run the MyDolphin Plus app, and I want to give credit where it’s due, because this is rare: in my testing, the app held its connection while both robots were underwater. Every cordless robot app I’ve tested — Beatbot, Aiper — dropped the second the robot submerged. With these two, I started cycles, switched modes, and steered the robot from the couch — mid-clean, every time. That’s how a smart pool robot should work.
But the two builds aren’t equal inside that app. The Sigma unlocks the deeper end of it — more control over how, when, and where it cleans. The Quantum Pro keeps the core set: schedules, modes, spot cleaning, manual steering. For most pool owners, the core set covers everything they’ll actually touch. If you’re the type who wants every dial and every mode, the Sigma is the fuller toolbox.
One detail I love on both: the weekly timer is built into the smart power supply itself. Never want to download an app? Push a button on the brick and the robot cleans on schedule anyway. In my opinion, that’s exactly how automation should be done.
Round three: Sigma.
Round 4 — Warranty and Build
Nobody makes thumbnails about warranties, and it might be the most expensive thing to get wrong. The Sigma carries a 3-year warranty. The Quantum Pro carries two. For context, most of the cordless robots I’ve reviewed — and even Dolphin’s own hugely popular Nautilus line — ship with a single year.
A pool robot sits in treated water, in the sun, doing physical work on a schedule. Warranty coverage is the manufacturer telling you how long they expect it to survive that job. An extra year on a machine in this class is real money — and it lines up with what’s inside the Sigma: three commercial-grade motors sharing DNA with Dolphin’s Wave units, the ones that clean public pools and resorts for a living.
Round four: Sigma.
Round 5 — Value
Now the Quantum Pro gets its swings in.
Look at everything that carried over from the top of the line. The same NanoFilters, which are still the best filtration I’ve tested on any robot — shine a light through the mesh screens most cordless units ship with and you can see what’s going to slip through; the NanoFilters grab particles those screens don’t even see. The same XXL top-loading MaxBin — pop the lid, lift the basket, no flipping a dripping robot on your deck. The same anti-tangle swivel cable — zero tangles in my testing, on either machine. And the HyperBrush active scrubbing, spinning about twice as fast as Dolphin’s base brushes, breaking loose the stuck-on grime before the suction ever grabs it.
That is most of the Sigma experience, at 1.9 PSI, for meaningfully less money. Dollar for dollar, the Quantum Pro is the strongest value in the ProLine, and in my opinion it isn’t close. BUT, you do get a shorter 2-year warranty on the Quantum Pro vs the Dolphin Sigma. I’d still give the slight edge to the Quantum, but the warranty being longer on the Sigma is something you may want to consider.
Round five: Quantum Pro.
Round 6 — Shallow Water
And here’s the one job the Quantum Pro does that the Sigma won’t touch. The Quantum Pro is built to clean sun shelves, baja ledges, and pool steps — Maytronics rates it for water as shallow as around 12 inches. In my testing, it climbed my steps, worked the shallow ledge, and came back down on its own. Was it flawless up there? No. But it’s one of the first robots I’ve tested that even attempts the job, and it gets it done. The Sigma was never designed for that territory. If you’ve been hand-brushing a sun shelf every Saturday, this round might outweigh everything else in this comparison.
Round six: Quantum Pro.
The Only Two That Pulled More — Premier and Clear UV
One more comparison, because I know the comments will ask. Only two robots have ever out-pulled the Sigma on my gauge — so let’s stack today’s contenders against both.
The Dolphin Premier is the raw-suction king of my logbook at 2.2 PSI — the strongest reading I’ve ever taken. It’s also the only Dolphin with a leaf bag: the Multi-Media system that swallows heavy leaf loads whole. But it skips the app entirely. So the Sigma gives up two-tenths of a PSI to the Premier and trades them for the app, the gyroscope navigation, and the top-load NanoFilters. If trees rule your pool, the Premier is still the answer — I’ve got a full Premier review and a Premier vs. Sigma comparison. If they don’t, the Sigma is the more complete machine.
Then there’s the Clear UV – a newer brand that I’ve tested — the most innovative robot to hit my test pool in years. Four motors, quad scrubbing brushes, and the headline feature: an ultraviolet light built into the bottom of the unit that disinfects the pool surface while it cleans. It posted 2.09 PSI on my gauge, sliding it right between the Premier and the Sigma. It’s the cutting-edge newcomer; the Sigma and Quantum Pro are the proven Maytronics platform with years of real-world reliability behind them. My full Clear UV review has the deep dive.
| Robot | Tested PSI (my gauge) | Notes |
|---|---|---|
| Dolphin Premier | 2.2 | Corded — leaf bag (Multi-Media filtration), no app |
| Clear UV | 2.09 | Corded — built-in UV disinfection, four motors |
| Dolphin Sigma | 2.0 | Corded — today’s contender |
| Dolphin Quantum Pro | 1.9 | Corded — today’s contender |
So the top of the mountain reads: Premier at 2.2, Clear UV at 2.09, Sigma at 2.0, Quantum Pro at 1.9. Four robots, all corded, separated by three-tenths of a PSI — and nothing battery-powered has cracked this tier.
What They Share — The Corded Advantage
Before the verdict, the thing these two share matters more than anything separating them: the cord. A cordless robot means fishing it out, hauling it to the charger, and dropping it back in — every single day. Call it 14 separate interactions a week. Either of these robots on the weekly timer? One. You rinse the filters once a week, and that’s the whole relationship. Fourteen versus one, all season long — over a summer, that’s the difference between owning a robot and working for one.
And on raw pull, remember: nothing battery-powered in my logbook has hit 2.0 PSI. My theory — and it’s the same thing you’ve felt with a cordless stick vacuum at home — is that battery-powered suction has a ceiling, and my gauge keeps backing that up. How much cordless suction fades as the battery drains is exactly what my drain-down test is measuring right now, so subscribe if you want those numbers the day they’re ready.
The Knocks on Each
Quick knocks on both, because no robot is perfect. The Sigma’s is price — and at this tier, it bugs me that the new Active Center Brush, the add-on that keeps it from hanging up on main drains, costs extra. When you’re paying flagship money, the performance parts belong in the box. If your current robot gets stuck on drains, I’ve got free fixes coming at ActuallyUsed.com/Robot-Stuck-On-Drain. The Quantum Pro’s knocks are the ones this whole comparison is about: a tenth less pull, a narrower bite, a year less coverage, and the lighter half of the app.
So Which Is Better, the Dolphin Sigma or Quantum Pro?
So where does that leave us? Six rounds. Four for the Sigma, two for the Quantum Pro. But rounds aren’t all worth the same, so let me say it straight.
The edge goes to the Sigma. Suction, intake width, app depth, warranty — those are the things a pool robot lives on every single cycle, for years. Based on my results, the Sigma is the most complete robot in Dolphin’s lineup: only the Premier and the Clear UV out-pull it on my gauge, nothing cordless comes close, and no other robot pairs this much power with this much filtration, navigation, and automation. If you want the better machine of the two and you plan to own it for the long haul, buy the Sigma. It’s the one I keep choosing to leave in my own pool — and around here, that’s the highest praise there is.
But the Quantum Pro walks away with something real: it’s the value pick of the entire ProLine. If the price difference matters to your budget — or your pool has a shelf or steps that need cleaning — the Quantum Pro hands you most of the flagship experience for meaningfully less. Just go in with clear eyes about the trade: a little less suction, a shorter warranty, and fewer app features. In my opinion, that’s a smart trade for the right pool — and the wrong one if what you want is simply the best, full stop.
Who Should Buy Which
Let me make it simple. Buy the Sigma if you want the strongest, most complete robot short of the Premier’s raw pull, you keep your equipment for years, and warranty length matters to you. Buy the Quantum Pro if your pool has a sun shelf or steps, you want ProLine filtration and automation without the flagship price, and the core app features cover what you’d actually use. If your pool is buried under trees, that’s Premier territory. And if your pool is under 33 feet with no shelf, save even more and look at the Cayman.
The best deals I can find on both of these are on the deals page. I’ve got standalone deep-dives on the Sigma and the Quantum Pro if you want every last detail, and the cordless battery drain-down video is up next — subscribe so you don’t miss it. Got a robot you want on the manometer? Tell me in the comments. Thanks for watching — I’ll catch you on the next one!
