ALDEX C-700 Series

C-700 Water Softening Resin Sodium Form

NSF/ANSI 44, 61 and 372 Certified. Aldex C-700 is a high capacity, high quality, gel-type cation resin capable of meeting the most exacting requirements of household, farm, commercial, institutional and industrial water softeners. It is supplied in the sodium form as black colored beads in 1 cubic foot bags and larger bulk packages.

Download Aldex C-700 Technical Bulletin (PDF)

Physical Chemical Properties

Resin Composition:Sulfonated styrene / divinylbenzene copolymer
Ionic Form as Shipped: Sodium (Na+)
Physical Form:Black colored beads
Moisture Content: 46-52%
Total Capacity:1.8 meq/ml minimum
40 kilograins as CaCO3 per cubic foot
Odor and Taste: None
Specific Gravity:1.26
Net Weight (as shipped): 50 lbs per cubic foot
Particle Size:16 to 50 mesh - Less than 0.5% through 50 mesh

Recommended Operating Conditions

Influent pH:No restrictions
Maximum Temperature:250 °F
Bed Depth:Minimum 24”
Normal 36”
Service Flow Rate:1 to 5 US GPM per cubic foot
Backwash Flow Rate:See Fig. 2
Regenerant:Sodium Chloride (NaCl) or Potassium Chloride (KCl)
Regenerant Strength:5 to 15%, usually 10%
Regenerant Flow Rate:0.3 to 1.0 US GPM per cubic foot of resin
Regenerant Contact Time:15 to 60 minutes
Regenerant Dosage Level: 2 to 15 lb per cubic foot
Slow Rinse (Displacement) Flow Rate:0.3 to 1.0 US GPM per cubic foot of resin
Slow Rinse Volume:20 USG per cubic foot resin
Fast Rinse Rate:1.0 to 5.0 US GPM per cubic foot resin
Fast Rinse Volume:30 USG per cubic foot resin

C-700 Features

No Clorinated Solvents

The absence of chlorinated solvents in the manufacturing of Aldex C-700 results in very low TOC leakage.

Very low color, taste or odor

Aldex C-700 meets the requirements for paragraph 173.25 of the Food Additive Regulation of the U.S. Food and Drug Administration.

High Capacity

30,000 grains of softening capacity when regenerated with 15 lbs of NaCl per cu. ft. and 20,000 grains with 6 lbs of NaCl per cu.ft. ensuring high efficiency and low operating costs.

Long Life

Strong and durable beads insure long service life.


Over 34 years of actual field usage by thousands of customers demonstrate the reliability of Aldex C-700.

Safety Information

A material safety data sheet is available for Aldex C-700. Copies can be obtained from Aldex Chemical Co., LTD. Aldex C-700 is not a hazardous product and is not WHMIS controlled.

Caution: Acidic and basic regenerant solutions are corrosive and should be handled in a manner that will prevent eye and skin contact. Before using strong oxidizing agents in contact with ion exchange resin, consult sources knowledgeable in the handling of these materials.


C-700 Operating Suggestions


Aldex C-700 will remove most of the dissolved iron, can filter much of the suspended iron and may or may not remove organically bound iron from water. When softeners are used to remove iron from the water, periodic cleaning of the bed mechanically or with a chemical iron cleaner may be necessary.


All cation exchange resins are affected by chlorine and suffer degradation and swelling. It is recommended that the chlorine in the water be maintained below 1.0 ppm when using Aldex C-700.

Fig. 1 Exchange capacity vs. regeneration level Sodium form C-700 Cation Resin

Backwash Characteristics

Aldex C-700 should be backwashed for at least 10 minutes after each service cycle in a conventionally down flow regenerated softener. To reclassify the beads and remove suspended solids from the top of the bed, the resin bed should be expanded at least 50% according to Fig. 2.

Fig. 2 Bed expansion vs. backwash flow rate for various water temperatures

In the case of non-conventional or upflow regenerated softeners, it may not be necessary to follow the above procedure since the backwash and brine injection are incorporated in the same step.

These suggestions and data are based on information we believe to be reliable. They are offered in good faith. However, we do not make any guarantee or warranty. We caution against using these products in an unsafe manner or in violation of any patents. Further, we assume no liability for the consequences of such actions.