Unless noted, specs and performance figures below come from the manufacturers.

The short version

Every whole house setup starts with sediment control, whether it gets its own housing or hides inside a bigger system. For most homes the best answer is a spin down prefilter, and the iSpring WSP is the one to beat: about $70, a reusable stainless steel screen in sizes from 50 to 1000 microns, and nothing to throw away. If your water carries fine silt instead of coarse grit, a disposable cartridge does the better job. If you are on a well that delivers serious sediment, skip straight to a backwashing system like the US Water Systems Matrixx. The sections below explain how to tell which water you have.

What sediment is, and what it does to a house

Sediment is the physical grit in water. It is sand and silt washed in from wells and reservoirs, rust flakes shed by aging city mains and old galvanized pipes, and mineral particles that break loose inside your own water heater. None of it is dissolved. Given a quiet glass and a few minutes, most of it settles to the bottom.

Left alone, sediment clogs the small screens in faucet aerators and showerheads. It scratches and wears the moving parts inside faucet cartridges, toilet fill valves, and washing machine and dishwasher inlet valves. It settles in the bottom of the water heater, where the layer of grit forces the heater to work harder and shortens its life. Most expensive of all, it plugs the fine filters downstream. A carbon cartridge asked to stop sand will choke on grit long before its carbon is used up. That is why sediment control is step one in nearly every system we cover, from the iSpring WGB32B to the SpringWell CF1.

Micron ratings in plain words

A micron is a unit of size, one millionth of a meter. A filter's micron rating is roughly the size of the smallest particle it is built to stop. For a sense of scale, a grain of fine sand is about 100 microns across, and the silt that clouds a glass of well water runs much smaller.

The practical ladder looks like this. A screen at 100 to 200 microns catches visible sand and rust flakes. A 50 micron screen catches fine sand. A 5 micron cartridge catches silt and the fine rust that tints water yellow. One caution applies at every step: finer is not automatically better. A filter that is finer than your water needs will clog quickly and drag on pressure, and iSpring itself warns that its 50 and 100 micron screens can clog very soon in water with a heavy sediment load. Match the rating to the grit you actually have, and step down only if the coarse stage lets too much through.

Spin down vs disposable cartridges

How a spin down filter works

Water enters a clear bowl and swirls around a stainless steel screen. The swirling action throws the heavy particles outward, they slide down the wall of the bowl, and they collect at the bottom, while the screen stops what the swirl misses. To clean it, you open the flush valve at the bottom and the collected grit washes out. There is no cartridge to buy, and iSpring rates the screen to last 1 to 2 years before it needs replacing. The limits are just as clear. Screens start at about 50 microns, so fine silt passes through, and someone has to open that valve. On a dirty well, that can be a weekly habit.

How a cartridge filter works

A cartridge pushes water through pleated or wound fiber media inside a housing. It catches finer material than any screen, down to 5 microns or less, which is why it is the design inside most multi stage systems. The iSpring WGB32B opens with a 5 micron sediment cartridge, and the SpringWell CF1 uses a 5 micron sediment prefilter after its tank. When a cartridge loads up, you throw it away and install a new one. The costs are modest but permanent. SpringWell's sediment filter runs about $21 every 6 to 9 months, and the sediment stage is part of the $125.99 annual cartridge pack on the WGB32B.

The verdict is simple. Choose a spin down filter for coarse grit and near zero running cost. Choose a cartridge for fine silt. On a dirty well, run both, spin down first and cartridge second, so the cheap screen takes the beating and the cartridge only handles what is left.

The picks

Best for most homes: iSpring WSP spin down filter

The WSP lists at $69.99 direct from iSpring, which buys a lead free brass head, a clear housing so you can see the sediment load, and a flush valve with a fitting for a garden hose. Screens come in sizes from 50 to 1000 microns, so start at 50 or 100 and adjust. Flow runs up to 20 GPM through the 1 inch fitting, which is more than any house will ask of a prefilter. iSpring also sells a larger WSP50B model with a built in scraper for the screen, and jumbo auto flushing models that flush themselves on a schedule set from a touch screen. Those cost several times more and suit owners who know they will not open a valve by hand.

Best cartridge route: the first stage you may already own

If you already run a whole house system, its sediment stage is this product, and there is nothing separate to buy. If fine silt is your only problem and you own no other system, a standalone cartridge housing in the same Big Blue format as the WGB32B stages is the cheap, effective route: a simple housing, inexpensive 5 micron cartridges, and better fine capture than any screen. Our iSpring WGB32B review shows the format in detail.

Best for heavy well sediment: US Water Systems Matrixx

When sediment arrives by the bucket, screens and cartridges become a chore schedule. A backwashing system takes the other path: the tank periodically reverses its flow and flushes the trapped sediment out to a drain, so there is no screen to scrub and no cartridge to swap. The Matrixx line runs from 5 to 25 GPM and from $1,325.50 to $1,775.50, and it is a full main system rather than a bolt on prefilter, which is why it anchors the well water spot in our best whole house water filter roundup. US Water notes that sizing must leave enough flow for the backwash cycle, so confirm that before ordering.

Placement: sediment always goes first

Install order on the main line runs like this: shutoff valve, then the sediment filter, then the softener or conditioner if you have one, then the carbon system, and the water heater splits off after that. Sediment goes first because it protects everything behind it, including softener resin and carbon media. It is also the filter you will service most often, so place it where you can reach it easily and fit a bucket under it. On a well, it installs after the pressure tank. Note that spin down housings are rated for indoor installation, so protect the unit from freezing and direct weather.

The honest limits

A sediment filter removes nothing dissolved

It will not touch chlorine, lead, PFAS, hardness, or bacteria. If particles are only part of your water story, the rest of the story needs other equipment. The fine end of the particle spectrum is its own category, covered in our guide to the best water filter for microplastics, and dissolved lead is covered in our whole house water filter for lead guide.

Fine silt beats coarse screens

If your complaint is cloudy water rather than grit you can feel, a 50 micron screen is the wrong tool. You need the 5 micron cartridge, and possibly a water test to find out what the cloudiness actually is.

Every sediment filter is a maintenance appointment

A spin down filter only works if someone flushes it, and a cartridge only works if someone changes it. A clogged sediment stage is the single most common reason owners report that a new whole house system killed their water pressure.

Who it is for

Well owners, owners of older city homes that see rust after main breaks or hydrant flushing, and anyone installing a carbon system or softener who wants the expensive media to last. If you keep fishing grit out of your faucet aerators, you are the audience.

Who should skip this

Homes on clean city water with no grit symptoms and no other filtration equipment may not need a standalone sediment unit at all. And if your only sediment is fine silt, skip the spin down format entirely and go straight to a cartridge.

Bottom line

Sediment filtration is the cheapest protection in the whole category and the layer everything else depends on. Buy the iSpring WSP if your grit is coarse and you want to stop paying for cartridges. Buy a cartridge stage if your problem is fine silt. Buy a backwashing system if your well delivers more sediment than either can keep up with. Then put it first in line and keep it clean.