Robotic pool cleaner comparison

Clear S vs Dolphin Sigma

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

Pool Express pick

Our pick: Clear S

Clear S is the Pool Express pick in this matchup. Clear S is listed $650 lower. Clear S includes a 59 ft cable with anti-tangle swivel.

Buy Clear S Compare every robot

Pool Express pick

CLEAR

Clear S

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

Current price $1,749MSRP ~~$2,749~~ Save $1,000

Buy Clear S

ProLine

Dolphin Sigma

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

Current price $2,399MSRP ~~$2,999~~ Save $600

Buy Dolphin Sigma

Pool Express pick

Why Clear S is our pick

Pool Express pick

Clear S

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

$1,749

Buy Clear S

Buying guidance

Clear S or Dolphin Sigma: our take

Clear S and Dolphin Sigma 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. Clear S lists 2 active brushes, Intelligent navigation (C9 microprocessor), and Quad (2 pump + 2 drive) motors. Dolphin Sigma lists 2 active brushes, SmartNav 3.0 with gyroscope navigation, and Triple commercial-grade DC motors.

Filtration and debris

Clear S includes UltraFilter; Dolphin Sigma includes Standard filter and NanoFilters. 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

Both models provide a weekly timer, smartphone control, and included remote control. Clear S uses a 59 ft corded cable with an anti-tangle swivel, while Dolphin Sigma uses a 55 ft corded cable with an anti-tangle swivel. Clear S is listed at 27.6 lb versus 24.6 lb for Dolphin Sigma; that 3 lb difference matters when lifting the robot from the pool.

Price, warranty and the decision

Clear S is listed at $1,749 and Dolphin Sigma at $2,399; Clear S is $650 less. Each lists a 3-year manufacturer warranty. Pool Express pick: Clear S. Clear S is listed $650 lower. Clear S includes a 59 ft cable with anti-tangle swivel. Choose Dolphin Sigma when it is the better fit for 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	Clear S	Dolphin Sigma
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	No	No
Automatic scheduling	Yes	Yes
Smartphone app	Yes	Yes
Anti-tangle swivel	Yes	Yes
3-year warranty	Yes	Yes
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 Clear S stands out

Clear S is the better fit for shoppers prioritizing the lower $1,749 starting price.

Is listed $650 lower
59 ft cable with anti-tangle swivel

Where Dolphin Sigma stands out

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

Uses a triple-motor cleaning system
Adds gyroscope-assisted navigation
Weighs 24.6 lb versus 27.6 lb