Pool owners often see terms like “150μm” or “50-micron filter” when shopping for a robotic cleaner — but what do those numbers actually mean? And how do they affect the cleaning performance?
This post explains the different micron ratings you’ll find in robotic pool cleaner and skimmer filters, what they capture, and how to choose the right one for your pool’s debris profile.
What Is a Micron?
A micron (μm) is one-millionth of a meter. It’s a unit of measurement used to describe the size of particles a filter can trap.
A 200μm filter can catch objects 0.2 millimeters in size — like pine needles, acorns, or small twigs
A 150μm filter is ideal for catching leaves, petals, dead bugs, and general debris
A 100μm filter starts to catch finer dust, broken-down organic matter, and smaller pollen clusters
A 70μm filter handles fine sand, light silt, and wind-blown dust from decks or patios
A 30μm filter captures most pollen, finer silt, and some suspended biofilm residue
A 10μm filter is necessary to trap very fine particles like algae spores or sunscreen residue
The lower the number, the finer the filtration — but also the faster it may clog if your pool has a lot of large debris.
Micron Ratings and What They Capture: A Visual Breakdown
| Micron Size | Debris Type | Example Debris |
|---|---|---|
| 200μm | 🍂 Large surface debris | Small twigs, pine needles, acorns |
| 150μm | 🍁 General pool debris | Leaves, bugs, flower petals, seed pods |
| 100μm | 🌬️ Finer organic debris | Dust, broken-down leaves, light pollen clusters |
| 70μm | 🏖️ Fine silt and dust | Sand, patio dust, fine grit |
| 50μm | 🧼 Light suspended particles | Cosmetic residue, small biofilm |
| 30μm | 🌾 Heavy pollen loads | Tree pollen (oak, maple, pine), suspended plant dust |
| 10μm | 🦠 Algae and spores | Algae spores, sunscreen, chemical cloudiness |
This visual breakdown gives you a clear idea of what each micron rating is capable of filtering. Pair it with the right cleaner and basket type to tackle the specific debris your pool collects.
Typical Filter Ranges by Cleaner Type
Different pool cleaning tools use different filter ranges, depending on what they’re designed to capture:
Robotic Pool Cleaners
Above ground models: Most of the above ground robots in our table list a 180μm main filter, ideal for leaves, bugs, and general pool debris. These filters offer a good balance of water flow and effective capture for casual and seasonal cleaning.
Inground models: Most of the inground robots in our table that list a main filter list 180μm. However, premium models often include dual-filter systems or interchangeable trays — one coarse (150μm) for larger debris and one ultra-fine (10–50μm) for fine silt, sand, or algae. This added flexibility helps tailor the cleaning approach to seasonal debris levels or specific water conditions.
Robotic Leaf Skimmers
150–200μm mesh trays — ideal for large leaves, insects, and surface debris
Not suitable for capturing sand or fine silt — they work best paired with a floor cleaner
Which Filter for Which Debris?
Match your filter type to your pool’s environment:
Trees nearby? Expect large leaves and debris — stick to 150–200μm
Windy or dusty location? A 70μm filter helps with fine particles and sand
Battling algae or cloudy water? Use an ultra-fine filter of 10 to 30μm to catch the clumps that come loose after treatment
💡 Tip: Always clean your filters after heavy use. Finer filters clog faster and reduce suction if not emptied regularly.
Can You Swap Filters?
Many mid-range and premium robotic pool cleaners support filter swapping. Some come with multiple baskets or layered trays, while others offer upgrade options sold separately.
Look for:
Snap-in trays or removable filter cartridges
Models with dual baskets or combo filters (coarse + ultra-fine)
Swapping filters seasonally can help you clean more effectively:
Use ultra-fine filters in spring and fall for pollen and algae
Use coarse mesh in summer when debris is larger and clogging is less frequent
Robots With Two Filters
Aiper Scuba S1
Cordless · Floor, wall, waterline · Up to 1,600 sq ft · In-ground and above-ground pools
Check price at AiperWybot C2
Cordless · Floor, wall, waterline · Up to 1,615 sq ft · In-ground and above-ground pools
Check price at WybotAiper Scuba X1
Cordless · Floor, wall, waterline · Up to 2,150 sq ft · In-ground and above-ground pools
Check price at AiperWybot C2 Vision
Cordless · Floor, wall, waterline · Up to 1,938 sq ft · In-ground and above-ground pools
Check price at Wybot
Aiper Scuba S3
Cordless · Floor, wall, waterline · Up to 1,600 sq ft · In-ground and above-ground pools
Check price at AiperAiper Scuba V3 Ultra
Cordless · Floor, wall, waterline, surface · Up to 3,875 sq ft · In-ground and above-ground pools
Check price at Aiper
Replacement Baskets and Fine Filters
A filter basket or filter tray is made for one model. Its shape, latches and seals are sized to that robot’s body, so a basket from another robot may not sit properly or seal around its edges, even with the same mesh size. A replacement should come from the maker, or match the part the manual names for your model. The mesh sizes earlier in this post tell you what a replacement will catch, but not whether it will fit. If you would like to see how the basket comes out on different robots, the guide to how filter baskets open on robotic cleaners explains the main designs.
Some robots list a separate fine filter in addition to the main basket. The table below holds 12 robots, with 9 in the Premium tier and 3 in the Pro tier. Aiper lists a 3-micron fine filter alongside the main basket of Aiper Scuba S1. Wybot pairs a 10-micron fine filter with the 180-micron basket of Wybot C2 Vision.
Because finer mesh clogs sooner, a fine filter earns its place only where the debris in your pool is fine, so check which fine filter your model’s manual lists before you order one.
The table below lists pool cleaners whose rows include a fine filter, with filters for the fine filter size, pool type and tier.
Pool Cleaners With a Fine Filter
| Check Price | Brand and Model | Fine Filter | Filter Access | Pool Type | Pricing Tier |
|---|---|---|---|---|---|
| Check Price | Aiper Scuba S1 | 3 μm | Top | In Ground | Premium |
| Check Renewed Price | Aiper Scuba S1 Pro | 3 μm | Top | In Ground | Pro |
| Check Price | Wybot C2 | 10 μm | Top | In Ground | Premium |
| Check Price | Poolmate Hydro 4 SE | 50 μm | Top | In Ground | Premium |
| Check Price | Poolmate Hydro 4 Cordless | 50 μm | Top | In Ground | Premium |
| Check Price | Poolmate Hydro 4 Corded | 50 μm | Top | In Ground | Premium |
| Check Price | Aiper Scuba X1 Pro Max | 3 μm | Top | In Ground | Pro |
| Check Price | Aiper Scuba X1 | ~3 μm | Top | In Ground | Premium |
| Check Price | Wybot C2 Vision | 10 μm | Top | In Ground | Premium |
| Check Price | Aiper Scuba S3 | 3 μm | Top | In Ground | Premium |
| Check Price | Aiper Scuba V3 | 3 μm | Top | In Ground | Premium |
| Check Price | Aiper Scuba V3 Ultra | 3 μm | Top | In Ground | Pro |
| No products found matching your criteria. Try different filters. | |||||
Specs provided for informational use only. Data may be incomplete or outdated. Read full disclaimer.
What About Algae and Very Fine Debris?
Algae spores range from 5μm to 30μm, depending on type. A filter holds a particle only if its openings are smaller than the particle, so the smaller spores slip through the 10μm to 50μm filters this post calls ultra-fine, while the clumps that come loose after treatment are caught.
However, filters alone aren’t enough to kill algae. You still need:
Proper chlorine levels
Algaecide treatment
Regular brushing and circulation
Use ultra-fine filters to capture what breaks loose after chemical treatment — it’s the final step in a full algae cleanup.
What About Pollen and Seasonal Surface Debris?
Pollen, flower petals, and seed husks are especially common in spring and early summer. Though not as small as algae, many types of pollen fall in the 10μm to 100μm range — too small for coarse filters to catch consistently.
Maple, oak, pine, and grass pollen often measure 30–50μm
Petals and seed casings may float and clog skimmer baskets — or require a robotic leaf skimmer
If your pool is near trees or flowering plants, consider running a fine or ultra-fine filter during high-pollen months. Skimmers can help reduce surface buildup before debris sinks to the floor.
Frequently Asked Questions
What does a 150-micron filter catch?
Leaves, bugs and other everyday pool debris. A 150-micron basket traps leaves, dead insects, flower petals and seed pods while water still flows freely through it. Some robotic cleaners list a main filter of 180 microns, which is a little coarser. Silt, fine dust and most pollen pass through both, so a pool that collects those needs a finer filter as well.
What is the difference between a 100-micron and a 200-micron filter?
The 100-micron filter catches finer debris. A 200-micron mesh stops particles of 0.2 millimeters and up, such as pine needles and small twigs. A 100-micron filter also holds dust, broken-down leaves and light pollen clusters. It fills and clogs sooner, though, in a pool that collects a lot of large debris.
How many microns is algae?
Most algae spores measure 5 to 30 microns. That is smaller than the mesh of a robot's standard basket. A filter does not kill algae. The cure is brushing, the right chlorine level and an algaecide. Once the treatment breaks it loose, algae often comes away in clumps larger than single spores, and an ultra-fine filter helps collect those.
Does a finer filter reduce suction?
It can, once it starts to clog. A fine or ultra-fine filter holds more small particles than a coarse basket, so it fills sooner, and then water passes through it more slowly. Empty and rinse a fine filter after every cycle. When most of what the pool collects is large debris, switch back to a coarse basket.
Can I rinse a robotic pool cleaner's filter with a hose?
Usually, yes. A garden hose on a gentle setting is the normal way to wash leaves and grit out of a filter basket or cartridge. Rinse until the water runs clear, and let the filter dry before you store it. Fine mesh is easier to damage than a coarse basket, so check your manual before you aim a strong jet at a fine filter.
👉 Next Steps
Robots With Two Filters
Aiper Scuba S1
Cordless · Floor, wall, waterline · Up to 1,600 sq ft · In-ground and above-ground pools
Check price at AiperWybot C2
Cordless · Floor, wall, waterline · Up to 1,615 sq ft · In-ground and above-ground pools
Check price at WybotAiper Scuba X1
Cordless · Floor, wall, waterline · Up to 2,150 sq ft · In-ground and above-ground pools
Check price at AiperWybot C2 Vision
Cordless · Floor, wall, waterline · Up to 1,938 sq ft · In-ground and above-ground pools
Check price at WybotAiper Scuba S3
Cordless · Floor, wall, waterline · Up to 1,600 sq ft · In-ground and above-ground pools
Check price at AiperAiper Scuba V3 Ultra
Cordless · Floor, wall, waterline, surface · Up to 3,875 sq ft · In-ground and above-ground pools
Check price at Aiper
Related Reading
Compare Cleaners by Filter Type and Micron Rating
Looking for something simple? Check out our page on floor-only robotic cleaners. These budget-friendly models stick to the pool floor, making them a great choice if you just want debris gone without the extras.
Want more than just floor cleaning? Explore our page on advanced robotic cleaners that scrub the walls and waterline too.
Want to find the right robotic cleaner based on filtration power? Use our filters to compare by:
Micron rating – 200μm to 10μm filters, based on what type of debris you want to trap
Skimmer or cleaner type – distinguish between floor-cleaning robots and surface skimmers
Debris needs – use the chart above to match filters to leaves, pollen, algae, or fine dust
Traction type and pool compatibility – choose between wheeled or tracked models, and match to above ground or inground setups