u/Futbol221

I found out my city uses chloramine and think it's fairly heavy at times if the year. I was going to get a RO with a catalytic carbon filter for the kitchen and a filter for the shower but I wonder if I can put a catalytic carbon filter on the main water supply so that I don't have to have an ugly filter on my shower and then just have a regular RO system in the kitchen. Does the filter on the main water supply have to have some kind of a pump?