Quick Answer: “Dolphin Proteus” covers three separate robots from Maytronics: the DX3 (about $629, floor + walls, 33 ft pools, no Wi-Fi), the DX4 ($1,099, floor + walls + waterline, 50 ft pools, no Wi-Fi), and the DX5i ($1,369, floor + walls + waterline, 50 ft pools, Wi-Fi). Confirmed directly against Maytronics’ own spec sheets: the DX4 and DX5i are otherwise identical — same suction, same coverage, same warranty — so the roughly $270 gap between them buys exactly one thing, the Wi-Fi app. Skip the app and the DX4 is the better buy for the same cleaning result.
If you searched “Dolphin Proteus” expecting one robot, here’s the short version: Maytronics sells three under that name, and the suffix changes what you’re buying more than the price alone suggests. Below is the plain-English breakdown of each tier, real 2026 prices, and which one actually fits your pool and budget.
The Proteus family at a glance
| Model | Cleans | Max pool | Wi-Fi | Weekly timer | Brushes | Price |
|---|---|---|---|---|---|---|
| Proteus DX3 | Floor, walls | 33 ft | No | No | 1 | ~$629 |
| Proteus DX4 | Floor, walls, waterline | 50 ft | No | Yes | 2 | ~$1,099 |
| Proteus DX5i | Floor, walls, waterline | 50 ft | Yes (MyDolphin Plus) | Yes | 2 | ~$1,369 |
Dolphin Proteus DX4
- Cleans floor, walls and waterline of inground pools up to 50 ft.
- 4,000 GPH suction — identical motor to the pricier DX5i, per Maytronics' own spec sheets.
- Weekly timer and 2 scrubbing brushes included; no Wi-Fi.
Robots this size usually ship freight, which can mean a multi-day wait — a free 30-day Amazon Prime trial can get one on your deck faster, and you can cancel before the trial ends if you don’t plan to keep it.
By the numbers
- Suction is flat across all three tiers: DX3, DX4, and DX5i all run the same 4,000 GPH motor per Maytronics’ own spec sheets — the same “coverage goes up, raw power doesn’t” pattern already confirmed across the Dolphin Explorer E10/E20/E30 trio and the Advantage family. Picking a pricier Proteus tier buys coverage area and features, not stronger cleaning.
- The DX4-vs-DX5i gap is exactly one feature: both are rated for the same 50 ft pools, the same floor-walls-waterline coverage, the same 2-year warranty, and both ship with a weekly timer and 2 scrubbing brushes — the only spec that differs, per Maytronics US, is Wi-Fi/MyDolphin Plus app access on the DX5i.
- Price spread: the three tiers span $629 to $1,369 direct from Maytronics, a more than 2x range — but roughly $270 of that (DX4 → DX5i) buys app control alone, not more cleaning.
- DX3’s real step-down: per Maytronics, the DX3 is rated for pools up to only 33 ft (vs. the DX4/DX5i’s 50 ft) and has a single brush instead of two — a genuine coverage cut, not just a missing convenience feature.
What “Proteus” actually buys you (and what it doesn’t)
All three Proteus models share the same 4,000 GPH suction motor — confirmed directly against Maytronics’ own product pages. What changes between tiers is pool-size rating, coverage area, and control method, not cleaning power.
Proteus DX3 — the smallest-pool, floor-and-walls entry point. At about $629 direct from Maytronics (third-party sellers like Poolbots list it closer to $669-$799), it’s the cheapest current Proteus-family robot, but it’s rated for pools up to only 33 ft and skips waterline scrubbing and the weekly timer entirely. It makes sense for smaller above-ground or compact inground pools where a pressure or suction cleaner isn’t already handling the walls.
Proteus DX4 — full coverage, no app, the value pick. At about $1,099 (third-party street pricing runs closer to $899-$1,199 per Poolbots), it jumps to 50 ft pools with full floor-walls-waterline coverage, a weekly timer, and a second scrubbing brush — everything the DX5i offers except Wi-Fi. For an owner who’s happy to run the robot on its built-in timer rather than from a phone, this is functionally the same robot as the DX5i for roughly $270 less.
Proteus DX5i — the DX4, plus the app. At $1,369, the DX5i adds Wi-Fi and MyDolphin Plus app control (remote start, scheduling, monitoring from your phone) on top of hardware that is otherwise identical to the DX4. Worth the premium only if phone control specifically matters to you. Note the naming: Maytronics’ current SKU is the “DX5i” — the “i” marks the Wi-Fi-connected version, and there’s no separate non-Wi-Fi “DX5” sold alongside it, even though some listings shorten the name to just “DX5.”
Which one should you buy?
If your pool is 33 ft or smaller and you don’t need waterline scrubbing, the Proteus DX3 is the cheapest legitimate entry into the Dolphin brand.
If your pool is up to 50 ft and you want full floor-walls-waterline coverage, compare the DX4 and DX5i on one thing only: do you want app control? If not, buy the DX4 — you’re getting essentially identical cleaning for roughly $270 less. If you do want to start or schedule cleanings from your phone, the DX5i is the one to buy, and the premium is a fair price for that convenience alone.
If you want a gyroscope-based navigation system instead of the Proteus line’s simpler scanning pattern, or more motors for faster cycle times, compare against the Dolphin Sigma or Dolphin Premier — both sit above the Proteus family and trade a real price jump for stronger navigation. For the full lineup across every Dolphin tier, see our best Dolphin pool cleaner guide, and for the wider market beyond Dolphin, our best robotic pool cleaner guide covers Beatbot, Aiper, Polaris, WYBOT and Hayward too.
The bottom line
“Dolphin Proteus” is three robots, not one. The DX3 (about $629) is the smaller-pool, floor-and-walls entry point. The DX4 ($1,099) and DX5i ($1,369) are mechanically near-identical full-coverage robots — the roughly $270 gap buys app control, nothing else. Unless you specifically want phone control, the DX4 is the smarter buy of the two.