Robotic pool cleaner comparison

Dolphin M600 vs Dolphin S300

A side-by-side comparison of pool fit, cleaning coverage, filtration, controls and the better Pool Express option.

By Brian Williamson, Pool Express product specialist
Updated November 9, 2026

Better alternative

A stronger Pool Express option

Dolphin M600 and Dolphin S300 are compared feature by feature below. For a stronger Pool Express option, consider Dolphin Quantum. Inground pools up to 50 ft that need floor, wall and waterline cleaning, with fine debris.

Buy Dolphin Quantum Compare every robot

M-Line

Dolphin M600

Inground pools up to 50 ft that need floor, wall and waterline cleaning, with fine debris.

Listed price $1,999

View better alternatives

S-Line

Dolphin S300

Inground pools up to 50 ft that need floor, wall and waterline cleaning, with fine debris.

Listed price $1,499

View better alternatives

A better alternative

What we recommend instead

Pool Express pick

Dolphin Quantum

Inground pools up to 50 ft that need floor, wall and waterline cleaning, with fine debris.

$1,649

Buy Dolphin Quantum

Buying guidance

Dolphin M600 or Dolphin S300: our take

Dolphin M600 and Dolphin S300 are compared on pool fit, cleaning reach, debris handling, controls and ownership details. The recommendation is based on the job the robot must do—not a simple feature count.

Pool fit and cleaning reach

Both robots are intended for inground pools. Both are rated for pools up to 50 ft. Each cleans floor, walls, and waterline, so coverage alone does not separate them. Dolphin S300's documented cleaning system includes 2 active brushes and CleverClean navigation.

Filtration and debris

Both models include Basket and UltraFilter. Both have documented fine-debris media, so basket capacity and ease of cleaning matter more than fine-particle capability.

Controls and day-to-day ownership

Dolphin M600 provides a weekly timer, smartphone control, and included remote control; Dolphin S300 provides a weekly timer and smartphone control. Both use a 60 ft corded cable with an anti-tangle swivel.

Price, warranty and the decision

Dolphin M600 is listed at $1,999 and Dolphin S300 at $1,499; Dolphin S300 is $500 less. Dolphin M600 lists a 3-year warranty compared with 2 years for Dolphin S300. Dolphin M600 and Dolphin S300 each have a specific fit, but neither is the Pool Express pick for this job. Our better alternative is Dolphin Quantum. Inground pools up to 50 ft that need floor, wall and waterline cleaning, with fine debris.

Feature check: what each robot actually has

A green check means the feature is documented as included. A red X means it is documented as absent. A dash means the source does not make the feature clear.

Feature	Dolphin M600	Dolphin S300
Cleans the pool floor	Yes	Yes
Climbs and cleans walls	Yes	Yes
Scrubs the waterline	Yes	Yes
Fine-debris filter included	Yes	Yes
Large-debris filter	Yes	Yes
Automatic scheduling	Yes	Yes
Smartphone app	Yes	Yes
Anti-tangle swivel	Yes	Yes
3-year warranty	YesEdge	No
No recharging between cycles	Yes	Yes
Built-in UV-C water treatment	No	No

Unknown is not treated as “no.” Specifications come from the product pages, current catalog records and manufacturer material collected for this site.

Where Dolphin M600 stands out

Dolphin M600 is the better fit for inground pools up to 50 ft that need floor, wall and waterline cleaning, with fine debris.

Carries a 3-year warranty instead of 2 years
3-year warranty

Where Dolphin S300 stands out

Dolphin S300 is the better fit for shoppers prioritizing the lower $1,499 starting price.

Is listed $500 lower
2-year warranty