Before the question can be answered ( Is an Iron Filter needed to treated the water ),
it's necessary to KNOW more about the water quality and planned usage ( how much water ),
AND if there is an Existing Water Softener, what size it is, and how it is set up to Regenerate.

QUESTIONS that need to be Answered before a Recommendation can be made:

1 ) What is the Size ( diameter and height ) or Capacity ( amount or grains of Resin ), if there is an existing Water Softener?

2 ) How often does it regenerate ( days or gallons settings )?

3 ) How much water is used ( or how many people normally use the water in the home )?

4 ) What is the water analysis ( what is quality of the water to be Treated )?
a ) What is the Hardness level of the source water ( grains per gallon or ppm )?
b ) What is the Iron level of the water Before Any Filters ( ppm = parts per million ).
AND the level After the Water Softener ( cold and hot water in the home ).
c ) What is the pH level of the incoming water ( there can be issues if below 7.0 or above 8.0 ).

*** IF you have a Water Softener - and have problems with Iron Staining,

There are several things that could cause you to still be getting staining.

1) It is critical that your system never runs empty of salt. If you run out, it can take several days ( and extra regenerations )
to get the water "good" again. Note: Hot water tank may retain some hard and iron water until drained or "turned over".

2) It is important that the time of day be kept correct and that no one uses water between
2 a.m. - 3 a.m. when the system is regenerating. While the system is in regeneration, any water
used would be unconditioned ( coming straight from the well ).

3) In high iron situations it is usually necessary to include a cleaner with the salt. Iron Out or Rust Out
( about 1/4 cup with each 80 lbs of Salt ) is commonly used. So is Tan-X
( Citric Acid, also 1/4 lbs per 80 lbs. ). A cup or two of Chlorine Bleach can be used, if your
softener DOES NOT have "white resins" installed for Tannic Acid Color removal
( this is a special layer of resins sometimes added to the regular resin inside your resin tank ).

4) It could be your resin tank is too small to handle all the iron.

5) It could be you are not regenerating often enough, or using enough salt per regeneration.
See this article, Frequency of Regeneration - How Often Should Softener Recharge?

6) On rare occasions the iron could be coming from just the hot water tank. I've seen a few
old ones ( over 20 years old ) rusting out on the inside, thus putting iron back into the water.
This is also true in older mobile homes ( again over 20 years old ) that used galvanized plumbing
under the trailer.


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Reference Article = Types of Iron Filters ( and the maintaining of them ).

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Iron Removal Options We Sell,

See:
Large sized Water Softener,
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