How to Pick the Right Pool Robot for Your Pool?

A hydraulic pool cleaner operates solely using the suction power generated by the pool’s filtration system. Its performance therefore depends directly on three key factors: the pump’s actual flow rate, the level of clogging in the filter, and the pressure available in the hydraulic circuit. As soon as one of these elements drops, the cleaner quickly loses both mobility and suction efficiency.

In a small, straightforward pool (rectangular shape, flat bottom), this type of cleaner can be sufficient. However, its limitations soon become apparent. As the filter begins to load up with debris, suction power falls sharply—and cleaning quality declines accordingly. The cleaner then struggles to maintain enough grip to climb the walls and properly scrub the waterline. As a result, vertical surfaces are only partially cleaned, becoming ideal areas for algae to develop and soil building up more quickly.

Finally, using a hydraulic pool cleaner requires a certain amount of preparation. Before cleaning can even begin, the hose must be fully primed with water to prevent air entering the system, correctly connected to the suction point, and the valves in the plant room adjusted to achieve the required flow rate. These steps are essential for proper operation but represent a noticeable setup time before each cleaning cycle.

Motorised, fully autonomous and equipped with their own suction system, electric and cordless robotic pool cleaners deliver comprehensive cleaning of the entire pool: floor, walls and waterline. However, their real performance does not depend on motor power alone, but on three technical factors that are often overlooked.

Suction flow rate (m³/h) influences how quickly debris is collected, but it does not, on its own, guarantee the capture of fine particles. On some models, a high flow rate can even be ineffective if the internal filtration is not designed to retain micro-impurities.

Navigation technology—whether random, gyroscopic or based on mapping—determines how thoroughly the pool is covered. Controlled movement avoids missed areas and limits unnecessary repeat passes, mechanically improving the overall efficiency of the cleaning cycle.

Filtration fineness (µ) depends on the quality of the filter media. Standard filter baskets typically offer a threshold of 50–60 µ, which is insufficient for mineral dust or very fine organic residues. High-performance models reach 5–10 µ, the level at which the robot genuinely starts to act on the root causes of cloudy water or algae-prone conditions.

In pools where water balance issues are frequent (unstable pH, insufficient disinfectant, heavy bather load, etc.), this ability to capture micro-particles becomes a decisive factor. It helps reduce the organic load and significantly lowers the risk of algae development.

Floating solar pool cleaners operate exclusively at the surface, where they collect pollen, dust, greasy films and other light debris. By removing these contaminants early, they help reduce the amount of pollution that would otherwise end up in the filter or gradually settle on the pool walls.

In pools exposed to wind, surrounding vegetation or heavy use, this surface pre-collection can help stabilise water quality by reducing the organic load between full cleaning cycles.

However, their scope remains limited. Unable to clean the pool floor, walls or hard-to-reach areas, they do not remove embedded deposits and can in no way replace an electric robotic cleaner. Their autonomy also depends on sunlight levels: under cloudy skies, early in the morning, late in the day or in shaded areas caused by covers, enclosures or dense vegetation, their power drops and navigation becomes inconsistent.

In practice, a solar pool cleaner is a useful supplementary tool for controlling the build-up of floating debris, but it is not sufficient on its own to keep a pool clean. It proves most effective in outdoor pools heavily exposed to pollen, airborne dust or surface films, provided it is used alongside manual cleaning of the pool floor and walls.

The shape of the pool imposes real constraints in terms of navigation, grip and stability—factors that are rarely detailed in technical datasheets. In a standard 8 × 4 rectangular pool, most robots provide acceptable coverage.

As soon as the pool features free-form shapes, steep slopes or complex areas, a robot equipped with a gyroscope or onboard mapping becomes essential to avoid blind spots. The difference is immediately noticeable: a poorly guided model repeats the same paths, while an intelligently steered robot optimises its movements and maintains consistent progress.

Submerged steps are a special case. Only a few models, designed with an adapted centre of gravity and effective inclination sensors, can climb onto them without slipping. The vast majority fail in this area, even when they are capable of climbing vertical walls.

For saltwater pools, material quality becomes a decisive criterion. Stainless steel fasteners, fully encapsulated motors and well-protected electronics are essential to prevent galvanic corrosion, which quickly affects entry-level models.

The most common mistake is choosing a so-called “universal” robot that leaves 10–20% of the pool untreated. Over the course of a season, these uncleaned areas become reservoirs for deposits and algae, largely undermining the value of the investment.

A robot priced at €300–400 can be suitable for a small, simple pool with limited exposure. However, as soon as pool complexity increases or usage becomes heavy, its lifespan drops quickly: three seasons is a realistic average under intensive use.

By contrast, a robot in the €900–1,200 range, properly matched to the pool and equipped with fine filtration, can last 5 to 8 years and often proves more cost-effective than replacing entry-level models multiple times.

An electric robotic cleaner requires a power supply protected by a suitable residual current device (RCD), as well as a socket positioned at a safe distance from the pool. Storage should be dry, well ventilated and protected from frost, in order to preserve the electronics and seals.

Water quality has a direct impact on both performance and component wear. In hard water (>25 °f), limescale gradually builds up on the brushes, reduces their flexibility and compromises grip on the pool walls. Regular use of a scale sequestrant and maintaining the pH between 7.0 and 7.4 help extend brush life, protect the impeller and ensure consistently effective cleaning.