I use the iron-removing stuff- usually about $13/bag or more locally .
Good reminder- I just put in my last 4 bags. Got caught short one time during Covid, and had to pay the Culligan guy $18/bag. But he had it.
I'll pick up 4 more bags today at the big box store - I like a reserve of at least 2 at all times since then. It doesn't spoil.
A tip for those who might benefit.
I don't need iron specific stuff.
Our system was about 7 years old and quit working, so I tore the head apart
and found some red scum. Seemed like iron residue, cleand it all up and
it seemed to work. But the system didn't. Then I recalled a friend that was in the water business telling us about Iron Out.
Bernie recommended everyone with a conditioner regularly using some, he claimed it kept the beads clean.
I bought some, treated the brine and cycled the system, daily for three days.
And it started working.
Since then, I put about a tablespoon on top of every block as I put them in the tank. As they settle the tank gets dosed block by block.
Haven't had an issue since 2008.
PS. Do not breathe the stuff. It is a fine dusty granule. The dust will
get you, and it is nasty!