Recommendations for water treatment?

[BigHatNoCattle]

Hi, all. I've read this forum for years and relied on a lot of information when I installed a water softener in 2013. We are in Indianapolis with a private water well and septic. My 2013 and 2023 water results:

Coliform bacteria: Absent (2013) / Present (2023)
E coli: Absent (2013 and 2023)

Barium (ug/L): 514 (2013) / 668 (2023)
Hardness (mg/L): 432 (2013) / 440 (2023)
Manganese (ug/L): 102 (2013) / 107 (2023)
Iron (ug/L): 3,110 (2013) / 3,160 (2023)
Calcium (ug/L): 113,000 (2013) / 117,000 (2023)
Magnesium (ug/L): 36,700 (2013) / 36,100 (2023)
Molybdenum (ug/L): n/a (2023) / 6.8 (2023)

Chloride (mg/L): 232 (2013) / 248 (2023)
Sulfate (mg/L): 70.4 (2013) / 36.2 (2023)

Turbidity (NTU): 0.02 (2013) / 0.11 (2023)

Fluoride (mg/L): 0.45 (2013) / BDL (2023)
Nitrate (mg/L): 0.85 (2013) / BDL (2023)
Zinc (ug/L): 42.5 (2013) / BDL (2023)

All other anions/metals/VOCs are BDL.

Both tests were taken after the pressure tank. Softener was in bypass mode for the 2023 test and the 2013 test was taken from an unsoftened line. I have been using only a water softener for the last 10 years and a reverse osmosis system for drinking water.

Main issues I'd like to address:

- Treat well for coliform (initial and/or ongoing)
- Water treatment for iron, hardness
- Sulfur smell from cold water

I'm in the early stages, but thinking of a setup like this: Pressure Tank -> Chlorination (or alternative) -> Iron Filter -> Water Softener -> RO for drinking water. I welcome any thoughts or recommendations.

Edit: I forgot to mention we have a Grundfos, 1/2 HP pump.

 

[Reach4]

Regarding coliform, you need special sampling techniques to avoid a false positive.

For any bacteria test to be meaningful, you have to follow proper sampling techniques including sterilizing the faucet. If you care about the coliform test results, care needs to be taken in sampling. There are variations on suggested sampling techniques, but they have some things in common:

https://www.doh.wa.gov/Portals/1/Documents/Pubs/331-225.pdf

https://axs-inc.com/wp-content/uploads/2021/10/TotalcoliformInstructionspdf.pdf

https://www.renogov.org/DocumentCenter/View/3801/KSU-Taking-water-samples-MF963

Water Sampling Procedures

These all describe methods to avoid contaminating the sample.

https://terrylove.com/forums/index....izing-extra-attention-to-4-inch-casing.65845/ is my well and plumbing sanitizing write-up.