SoftPlus Water Softeners Iron Rival Iron Reduction Systems ecoTAC Hard Water Conditioning Systems

Dow Filmtec NF90-400 Nanofiltration Membrane

up to 9,500 GPD replacement nanofiltration membrane element

The Filmtec NF90-400 nanofiltration element is a high area, high productivity element designed to remove a high percentage of salts, nitrate, iron and organic compounds such as pesticides, herbicides and THM precursors. The high active area membrane combined with low net driving pressure of the membrane allows the removal of these compounds at low operating pressure.

Membrane Type:Polyamide Thin-Film Composite (TFC)
Maximum Operating Temperature:113F (45C)
Maximum Operating Pressure:600 psi (41 bar)
Maximum Pressure Drop:15 psi (1.0 bar)
Maximum Feed Flow Rate:70.0 gpm (15.9 m3/hr)
pH Range, Continuous Operation:2-11***
pH Range, Short-Term Cleaning:1-12* (30min)
Maximum Feed Silt Density Index:5 SDI
Free Chlorine Tolerance:<0.1 ppm**
Permeate Flow Rate:MgSO4: 9,500 GPD (36 m3/day)*
NaCl: 7,500 GPD (28.4 m3/day)*
Stabilized Salt Rejection:MgSO4: >97%
NaCl: 85 - 95%

*Permeate flow and salt passage based on the following test conditions: 2000 mg/l NaCl, 70 psi (0.48 MPa), 77C (25C) and 15% recovery. 2000 mg/l MgSO4, 70 psi (0.48 MPa), 77C (25C) and 15% recovery. Flow rates for individual elements may vary +/- 15%.

**Under certain conditions, the presence of free chlorine and other oxidizing agents will cause premature membrane failure. Since oxidation damage is not covered under warranty, Dow recommends removing residual free chlorine by pretreatment prior to membrane exposure. Most RO systems have carbon pre-filters for this purpose.

***Maximum temperature for continuous operation above pH 10 is 95F (35C).

Filmtec NF90-400 Nanofiltration Membrane


   A: 40.0" (1,016mm)
   B: 1.5" (38mm)
   C: 7.9" (201mm)
Filmtec NF90-400 Size Chart
Model Diameter Inches Length Inches Active Surface
Area ft2 (m2)
Test Pressure Permeate Flow
GPD (m3/day)
(w/ Free Shipping)
Filmtec NF90-400
Our Stock #703149985
Dow Part #149985
8 40 70 (4.8) 400 (37) up to 9,500 (36)

Notice: The use of this product in and of itself does not necessarily guarantee the removal of cysts and pathogens from water. Effective cyst and pathogen reduction is dependent on the complete system design and on the operation and maintenance of the system.

Customer Questions & Answers

No customer questions have been submitted for this. Have a question? Ask it above.