Robot pool cleaner filtration explained: what a micron rating covers

What the number describes

A micron rating is a claim about particle size: the smaller the figure, the finer the debris a filter layer is stated to capture. Sand, hair, and pollen sit at very different sizes, so the rating is genuinely useful information. The problem is that it is published as one number for a component that is often several components, and different makers pick a different one of those components to print.

Across the models we publish pages for, the published figures run from 3 microns to 180 microns, which looks like a sixty-fold spread in filtration quality. It is not. Some of those numbers describe an ultra-fine layer sitting downstream of a coarse basket, and some describe the only basket in the machine. Below, each figure is quoted with the layer its maker assigns it to, and where a maker's own pages disagree we say so rather than pick the flattering one.

The finest layer is not the whole filter

Aiper publishes the finest figures we track, and both come with a layer attached. The Scuba S1 Pro is published as dual layer filtration where Level 1 is a 180 um fine filter basket and Level 2 is a 3 um MicroMesh ultra fine filter, with a top load 5 L debris basket. The Scuba S1 is published the same way: a 180 um fine filter basket plus a 3 um MicroMesh ultra-fine filter, in a 3.5 L basket. In both cases the 3 um figure is the ultra-fine secondary layer, not a rating for the filter as a whole.

That distinction is not academic on Aiper's own site. The comparison table on the Scuba S1 Pro store page lists only the 180 um layer for the Scuba S1, so the same maker publishes the same robot at 3 microns in one place and 180 in another, depending on which layer the table is describing. We record the finest published layer and note the conflict, which is the only way to keep the S1 comparable with its own sibling.

The Wybot C2 Vision is built the same way at a coarser second stage: dual layer filtration published as a 180 um large cartridge plus a 10 um ultra fine filter, with 10 um the finest published layer. So the three finest numbers on this site, 3, 3, and 10 microns, all describe a second stage behind a 180 micron primary. Compared against a machine that publishes one number for one basket, they are not measuring the same thing. Our chart labels its axis finest layer to keep that honest, and how to choose a robot pool cleaner covers the same trap alongside the other specs.

• Aiper Scuba S1 Pro: 3 um ultra-fine Level 2 behind a 180 um Level 1 basket, 5 L top load.
• Aiper Scuba S1: 3 um MicroMesh ultra-fine behind a 180 um fine filter basket, 3.5 L basket.
• Wybot C2 Vision: 10 um ultra fine behind a 180 um large cartridge.

Single-rating filters and multi-basket sets

Three models publish 180 microns as their finest rating, with no finer secondary layer claimed. Aiper's Seagull Pro is published in the store spec-comparison table as Filtration Spec. 180um, which is the single standard filter-basket rating; unlike the Scuba S1 Pro, it has no published ultra-fine secondary layer, and its basket is a 7 L top load, the largest published capacity among the models we publish pages for. Aiper's Scuba SE is published as a 180 um Fine Filter Tray with debris stored in a 2 L chassis tray. The Wybot S2 Solar is published as a 180 micron Regular Filter Basket plus a 40 ppi sponge, and while Wybot's marketing describes a 3D Adsorption System with an ultra-fine sponge, 180 microns is the finest micron-rated layer it publishes. A sponge with a ppi rating is not a micron rating, and we do not convert one into the other.

Beatbot publishes 150 microns across its line, on a basis that changes slightly per model. The AquaSense 2 Pro is published as a two-layer filter of 150um plus 250um, stated to capture particles as small as 150 micrometers, in a 3.7 L filter basket. The AquaSense 2 Ultra ships dual filter baskets published as larger baskets at 150um plus 250um and thinner baskets at 250um, so which rating applies depends on which basket is fitted; we record the finest published rating. The AquaSense 2 publishes 150 um in its FAQ with a 2 L filter basket in the spec table, though two FAQ entries describe the filter inconsistently as single layer and as two layer, both at 150 um.

Read across those two groups and the picture is clearer than the raw numbers suggest. A 150 micron Beatbot rating is the finest layer of the filter you get, and a 180 micron Aiper or Wybot rating is likewise the finest layer published. Those six are broadly comparable with each other. The 3 and 10 micron figures are not comparable with them, because they name a different stage.

• Aiper Seagull Pro: 180um single standard basket rating, 7 L top load.
• Aiper Scuba SE: 180 um Fine Filter Tray, 2 L chassis tray.
• Wybot S2 Solar: 180 micron Regular Filter Basket plus a 40 ppi sponge.
• Beatbot AquaSense 2 Pro: 150um plus 250um two-layer, 3.7 L basket.
• Beatbot AquaSense 2 Ultra: 150um plus 250um larger baskets, 250um thinner baskets.
• Beatbot AquaSense 2: 150 um per the FAQ, 2 L basket per the spec table.

Where no micron rating is published

The Polaris EPIC 8642 iQ publishes no micron rating at all. What Polaris does publish is a filter canister capacity of 4 L (about 1.1 gal) with a transparent window that shows when the canister is full. That is a real and useful spec, and it is not a filtration fineness figure. Polaris also publishes no flow rate for the model, describing Cyclonic Vacuum Technology without giving a GPH number, so neither half of the filtration picture can be read off its sheet.

We do not fill that gap. There is no industry default micron rating to assume, no way to derive fineness from canister volume, and no basis on which to borrow a figure from another Polaris product or a replacement-cartridge listing. The finding is that the rating is not published, and a buyer who cares about fine debris should know that before ordering rather than after.

What a published micron figure cannot tell you

Even where a number exists, it is narrower than it looks. None of the makers we track publishes a capture efficiency, a test standard, or a percentage of particles retained at the stated size, so a 150 micron claim means the layer is described as capturing debris at that size, not that it removes a stated share of such particles from your pool. None publishes how the rating degrades as the basket loads with debris, which is the condition a filter spends most of a cleaning cycle in. And none publishes filtration performance separately from flow, even though the two interact.

Flow itself is published loosely enough to reinforce the point. Wybot's own pages give the C2 Vision as 3,592 GPH in a comparison table and 3,883 GPH in a marketing bullet on the same page, with the spec section carrying a laboratory environment, reference only disclaimer; we chart the tabular 3,592. Beatbot publishes 5,500 GPH for the AquaSense 2, 2 Pro and 2 Ultra but footnotes it as the highest rate tested in its internal labs, a peak lab figure rather than a rated continuous flow. Aiper's Scuba S1 Pro spec table publishes 6,000 GPH (22,740 LPH) while a comparison table on the same store page says 6,600 GPH. Wybot is the one maker to label a flow figure as an average, publishing 3,962 GPH for the S2 Solar as an average suction rate.

The workable rule: compare micron figures only within the same stage, treat basket capacity as a separate convenience spec, and read any filtration or flow number as an attributed manufacturer claim about a component. For the models rated for smaller vinyl-walled pools, robot pool cleaners for above-ground pools covers which of these filters ship on above-ground-rated units.