Fujian Huamo Technology Co., Ltd. is one of the most reliable manufacturers and suppliers of under sink reverse osmosis membrane in China. If you're going to wholesale bulk under sink reverse osmosis membrane made in China, welcome to get catalog and price list from our factory. All custom made products are with high quality and competitive price. Also, OEM service is available.
Product Details
The under sink reverse osmosis membrane addresses three real‑world under‑sink issues:
Noise reduction – The feed spacer uses a proprietary diamond‑pattern design that minimizes water turbulence, reducing the characteristic "hissing" sound during drain cycles. This makes the membrane suitable for open kitchens or shared walls with bedrooms.
Moisture resistance – The outer wrap is coated with a food‑grade moisture barrier to prevent wicking of humidity into the membrane layers, which can happen under sinks with leaky pipes or high humidity (e.g., dishwashers nearby).
Easy gripping surface – The end caps have a textured ring to help you pull out the old membrane without pliers – a common struggle when replacements are stuck due to calcium buildup or tight fit.
As a low pressure RO membrane element supplier, we designed this element to operate efficiently at 60‑65 psi, the typical pressure of residential water lines without the need for an additional booster pump – one less device to fit under your sink.
Video Description
See how our under sink RO membranes are assembled, tested for leak‑proof seals, and packaged for easy installation. Each element is inspected for dimensional accuracy to ensure a snug fit into standard 1812 housings.
Product Specifications
Parameter | Value |
Membrane size (D×L) | 1.8″ × 12″ (1812 format) – fits all standard under-sink housings |
Flow rate rating | 50 or 75 GPD (both available) |
Stable salt rejection | ≥97% (ULP) / ≥98% (HP) at 60 psi, 25°C, 250 ppm NaCl |
Max operating pressure | 300 psi |
pH range (continuous) | 3 – 10 |
Free chlorine tolerance | <0.1 ppm (carbon pre-filter mandatory) |
Active membrane area | 4.2 ft² (0.39 m²) |
Package type | Dry – no preservative liquids, no sticky residues |
Installation note: Flush for one hour before first use. Use a flow restrictor matching the membrane's GPD rating (color‑coded blue for 50 GPD, purple for 75 GPD).
*Performance measured under standard test conditions. Real output varies with feed water pressure and temperature.
Why This Under Sink Membrane Is the Practical Choice
- No tool replacement – The textured end cap and anti-stick outer wrap mean you can pull out the old element by hand, even if it has been in place for 2+ years.
- Quiet drain cycle – The diamond-pattern spacer reduces noise by about 30% compared to standard straight-channel designs – tested in a real under-sink cabinet with a decibel meter.
- Humidity-hardened outer layer – The membrane does not absorb ambient moisture, preventing swelling that can make the element impossible to remove.
- Compatible with all standard 1812 housings – This Replacement RO Membrane works with APEC, iSpring, Express Water, AmazonBasics, and no-name Chinese housings. If your housing is 1.8" inside diameter, it fits.
- No plumbing mods for capacity upgrade – Swap a 50 GPD membrane for a 75 GPD membrane without changing the housing or fittings – just replace the restrictor if needed.
- As a domestic RO membrane 1812 manufacturer, we individually test each batch for flow consistency and leak-proof seals before shipping.
Ideal Use Cases
- Under‑sink RO systems in apartments with limited cabinet space
- Kitchens where dishwasher and RO share the same cabinet (humidity exposure)
- Households sensitive to noise (open floor plans, near bedrooms)
- DIY replacements where the user does not have tools or experience to force stuck membranes
FAQ
1. The old membrane is stuck and won't come out. How does this membrane prevent that?
Most stuck membranes are due to swelling from absorbed moisture or hardened calcium deposits. Our under sink reverse osmosis membrane uses a hydrophobic outer wrap that does not absorb humidity. The surface is also coated with a food-grade release agent that prevents bonding to the housing wall. For removal, we include a small plastic pull-tab on the end cap – just hook it with a finger and pull straight out.
2. My under-sink area is very tight – I can barely fit my hand to turn the housing. Is installation still possible?
Yes. The membrane requires only 3 inches of clearance in front of the housing to slide the element in and out. The O-rings are pre-lubricated with dry silicone (no messy grease), and the brine seal is designed with a low-insertion-force lip. Most users can replace it in under 5 minutes using only their fingers.
3. I hear a gurgling or hissing sound from my RO system, especially when the tank fills. Will this membrane make it quieter?
The noise usually comes from the flow restrictor and the membrane's drain channel. Our diamond-pattern spacer reduces turbulence, but if the noise persists, check that your restrictor is not clogged. Some customers also pair this membrane with a quiet-type flow restrictor (sold separately) for near-silent operation.
4. How often should I replace an under-sink membrane? And how do I know it's time?
Every 12-24 months, or when you notice: (a) product water TDS has doubled from the initial reading, (b) flow rate drops significantly (e.g., takes more than 5 seconds to fill a cup), or (c) the water has a musty taste – which can indicate bacterial growth inside the element. This residential RO membrane element comes with a date sticker on the label; write your installation date for easy tracking.