Robots That Filter Fine Dust and Algae (50 Microns or Finer)
Cloudy water that the pool filter will not clear is usually particles under 50 microns: fine dust, silt and the first stage of algae. Most robots ship with a 150 to 180 micron basket, which catches sand and leaves and lets all of that straight through. The robots below put a finer layer in the box. Two practical costs come with it: an ultra-fine layer clogs faster, so it needs rinsing after nearly every run, and several makers recommend the coarse basket alone after a storm so the fine one does not blind.
How this list is ordered: Every robot whose in-box filter the maker rates at 50 µm or finer, ordered by that rating and then by price. Optional filters sold separately do not count. 5 of the catalog’s robots qualify.

1Aiper
~$650Aiper Scuba S3
Aiper's S3 brings the 3-micron ultra-fine layer down to $650 and parks at the waterline for retrieval.
- Finest filter
- 3 µm
- Pool fit
- ~79 ft (floor only)
- AiperScuba X1Cordless floor+wall+waterline
2Aiper
~$800Aiper Scuba X1
Aiper's X1 scrubs horizontally up to two inches above the waterline, pulls 6,600 gallons an hour through a five-litre basket and a 3-micron MicroMesh layer, and charges on a wireless dock.
- Finest filter
- 3 µm
- Pool fit
- ~55 ftclaims ~66 ft

3Aiper
~$1,000Aiper Scuba S1 Pro
The S1 Pro adds a 3-micron ultra-fine layer under the 180-micron basket, horizontal waterline scrubbing, the Aiper app and a 66-foot rating to the S1 recipe.
- Finest filter
- 3 µm
- Pool fit
- ~55 ftclaims ~66 ft

4WYBOT
~$500WYBOT C2
WYBOT's 2026 C2 puts a 10-micron ultra-fine filter behind its 180-micron cartridges for $500, and returns to the pool edge when it is done.
- Finest filter
- 10 µm
- Pool fit
- ~68 ft (floor only)

Other shortlists
- Cordless Robots With the Battery for a 16 × 32 In-Ground Pool
- Robots Rated for Above-Ground Pools
- Corded Robots That Scrub the Waterline for Under $1,500
- The Easiest Robots to Get Out of the Pool
- Solar Robotic Skimmers, by Filter Mesh
- Floor Robots With the Lowest Cost per Warranty Year
- Cordless Robots Rated for Bigger Pools Than Their Battery Covers