Hi roadrunner,
I have the same problem as you - with medium hardness as well.I got a FE 1054 filter (& a carbod filter) put in 3 weeks ago by Paddy Butler, Clonroche, Wexford - (I am not affialiated).The filter seems to be working.The agreement I have with them is 4 - 6 weeks after the filter is installed I get the water independently tested and assuming all is ok I pay the money.
I am in the house about 1.5 years and the genius who installed the water pump put in a water filter.This filter is completely unsuitable for the task and apparently is only suitable to remove hardness.(If you want I can PM you his name so you can avoid him). There was a serious amount of brown residue in the storage tank in the attic. I cleaned it out and the there is no residue in the tank now - so as I say it's looking good.
The filter media is "manganese greensand". This sand will have to be replaced in 7 - 10 years - the main body should last a lifetime.
I had also looked at an aeration filter but preferred to stay local.The filter I have also removes sediment.
If you are not in a major hurry you could also take a punt and import from USA. Excellent prices right now and get a local plumber to fit it for you. I was in a hurry as I wanted to get the problem before a baby was born - not because the iron would hurt it but a possible lack of time after the baby being born.
Hope the helps,
Wexford dude