Membrane Solutions 5 Micron 10"x2.5" String Wound Whole House Water Filter Replacement Cartridge Universal Sediment Filters for Well Water - 6 Pack

Why I tried this filter

Sediment has always been the weak point in my well-fed system. After a pump replacement stirred up the line, my first-stage 10-inch cartridge would blind off quickly and the house would see slow faucets and cranky appliances. I swapped in the Membrane Solutions string-wound 5‑micron cartridges as my new first defense, expecting better dirt-holding than the usual melt‑blown cartridges I’d been using. After several months of real-world use, they’ve earned a spot in my maintenance routine.

Build and compatibility

These are classic 10 x 2.5-inch string‑wound cartridges made from food‑grade polypropylene with a polypropylene core. They drop straight into any standard 10-inch housing—the typical clear or blue sumps found on most whole-house prefilters and under-sink RO prefilters. No adapters or fuss.

The winding is tight and uniform, and the gradient density is evident: more open on the exterior to catch larger particles and tighter toward the core for finer capture. That depth profile is the main reason to choose string‑wound in the first place; it keeps the outer layers from plugging immediately so the inner layers can work steadily. Material-wise, they’re lead- and BPA‑free, and the media is tested to NSF/ANSI 42 for material safety. That’s not performance certification; it means the materials are safe for contact with potable water and won’t leach odors or off‑tastes. That matches my experience—no plastic taste, no smell, just cleaner water.

Installation and first flush

Installation was uneventful: shut off the inlet, relieve pressure, spin off the sump, drop the cartridge over the standpipe, and snug the housing back on after checking the O‑ring. I always smear a bit of silicone grease on the O‑ring and clean the seating surface; it pays off the next time you open the housing.

After replacing a cartridge, I flush for a few minutes at a laundry sink. With these, the initial water was clear within seconds. No visible fiber shedding or cloudiness. If your housing doesn’t indicate flow direction, assume outside‑in for string‑wound. That yields the best use of the depth gradient and makes it easy to assess loading—the outside surface darkens as it grabs rust and silt.

Filtration performance

As a first-stage whole-house filter, these do exactly what they should: take the hits from rust, sand, and silt before the carbon and softening equipment see it. On my iron‑bearing well, the outer layers turned orange‑brown quickly (a good sign), while fine particulate that used to sneak through to the next stage was substantially reduced. Showers cleared up, and the carbon block downstream stayed visibly cleaner at change‑out.

I also tried a cartridge ahead of a UV disinfection unit on a rain catchment line. UV systems like low turbidity; this cartridge kept the water noticeably clearer between storms, and the UV sleeve stayed clean longer. If you’re feeding a reverse osmosis system, this is a solid first stage—RO membranes are happier when grit is removed upstream.

It’s important to note what a 5‑micron nominal rating means: it’s designed to catch most particles around that size and larger, but not colloids or dissolved contaminants. For high levels of ultra‑fine silt, stepping down to 1 micron (with the caveat of faster fouling) may be necessary. For typical well water with mixed particle sizes, 5 micron is a practical balance between protection and flow.

Flow and pressure behavior

The biggest difference I noticed versus typical melt‑blown cartridges was how the pressure drop stayed stable longer. With melt‑blown, I’d see a sharp decline after a week of heavy sediment. The string‑wound design loads gradually, so household flow remained consistent across showers, laundry, and the dishwasher. I run a small pressure gauge before and after the housing; when the differential climbed noticeably, it was time to swap. Until that point, the system felt almost transparent.

If your plumbing or appliances are sensitive to pressure (tankless heaters, for example), this steadier behavior is a real benefit. Pleated filters can offer even higher initial flow but don’t always catch fines as effectively, and they’ll clog quickly if the sediment load is heavy and varied.

Lifespan and maintenance cadence

The stated capacity is roughly 15,000–20,000 gallons, but true life depends entirely on your incoming water. On my well, with occasional turbidity spikes after heavy rain, a cartridge lasted about three months before the pressure differential nudged me to change it. On the cleaner rain line, I pushed to five months. If your water is relatively clear, six months is reasonable; if you’ve just done pump work or had line repairs, keep spares on hand and expect quicker change‑outs until things settle.

Cartridges in this six‑pack make it easy to stay ahead of maintenance. I write the installation date on the housing with a paint marker and keep a pair of inexpensive liquid‑filled gauges before and after the filter to avoid guessing. If you don’t have gauges, “slower showers and longer washing machine fills” is your practical clue.

How it compares to other 10-inch sediment cartridges

• Versus melt‑blown polypropylene: The string‑wound holds more dirt and maintains flow longer, especially with mixed particle sizes. Melt‑blown can be fine for cleaner municipal water; on a dirty well, I prefer string‑wound.
• Versus pleated polyester: Pleated filters have high surface area and are sometimes rinsable, but they’re better for coarse, uniform particles and lighter loads. For fines and variable sediment, pleated elements can blind quickly. I keep pleated on hand for temporary post‑repair cleanups; for everyday use, these string‑wound cartridges win on consistency.
• Versus graded density “premium” cartridges: The performance here is competitive, without a premium price tag. The absence of molded end caps hasn’t been an issue; the wound construction and core are sufficiently rigid for typical residential pressures.

What it won’t do

These are sediment filters. They won’t remove chlorine, chloramine, organic chemicals, or improve taste on their own. They won’t reduce dissolved metals like arsenic or lead. They aren’t microbiological filters. If those are your targets, pair this first stage with the right second stage, such as a carbon block for taste and odor, a catalytic carbon or KDF cartridge for chlorine and some metals, an iron filter for ferrous iron, or a dedicated arsenic system. Used that way, this cartridge protects the pricier stages and extends their life.

Value and packaging

Buying in a six‑pack brings the per‑filter cost down, and the quality is consistent across cartridges. Each one arrived clean and intact, wound tightly with no loose strings. After cycling through multiple filters, I haven’t seen core deformation or media collapse—even at higher flow events like lawn irrigation.

Small drawbacks

• No performance certification claim: The NSF mark here is for material safety only. That’s common at this price point, but worth knowing if you’re expecting a performance‑certified rating.
• Not absolute micron: Like most residential sediment cartridges, this is a nominal 5‑micron filter. If you need guaranteed capture of very fine particles, you’ll want a tighter (and usually more restrictive) stage downstream.
• Occasional variability in lifespan: This isn’t a fault of the filter so much as the nature of string‑wound and variable source water. If your well’s sediment load swings, your replacement interval will, too.

Who it’s for

• Homeowners on well water looking to protect downstream filters, softeners, and appliances from grit, rust, and silt.
• Pre‑RO users who want to keep membranes free of particulate.
• Rain catchment and UV pre‑treatment setups that need steady turbidity control without severe flow penalties.
• Anyone with a standard 10-inch, 2.5-inch housing who wants dependable sediment removal and predictable maintenance.

Recommendation

I recommend the Membrane Solutions string‑wound 5‑micron filter for whole‑house and pre‑RO sediment control in standard 10-inch housings. It fits reliably, filters effectively across a range of particle sizes, maintains flow longer than basic melt‑blown cartridges, and offers good value in a six‑pack. It won’t address taste, odor, or dissolved contaminants, but as a first‑stage workhorse to protect the rest of your system, it’s exactly what I want: predictable, low‑maintenance, and safe. Pair it with the right downstream media for your specific water chemistry, and you’ll get clearer water, fewer clogs, and longer life from the rest of your filtration stack.