Here are a couple of filtration options for the contaminants you mentioned. The 3 stage system will be more effective at reducing sediment and also will help to preserve the chloramine filter by getting more sediment out of the water before it reaches the chloramine filter. Since the chloramine filter is more expensive, this should reduce the time between changes. The time between filter changes will depend on how much water you use and the levels of these contaminants in your water.
3 Stage whole house system:
http://www.waterfilters.net/Pentek-BBFS-222-Three-Housing-Water-Filter-System_p_0-588.html
Stage 1:
http://www.waterfilters.net/culligan/wholehouse/replacement_filters/DGD-7525-20.htm (20 micron sediment filter)
Stage 2:
http://www.waterfilters.net/culligan/wholehouse/replacement_filters/DGD-5005-20.htm (5 micron sediment filter)
Stage 3:
http://www.waterfilters.net/Pentek/wholehouse/Specialty_Filters/CRFC-20BB-Filter.htm (Chloramine & Chlorine Filter)
2 Stage whole house system:
http://www.waterfilters.net/Pentek-BBFS-22-Water-Filtration-System_p_0-586.html
Stage 1:
http://www.waterfilters.net/culligan/wholehouse/replacement_filters/DGD-5005-20.htm (5 micron sediment filter)
Stage 2:
http://www.waterfilters.net/Pentek/wholehouse/Specialty_Filters/CRFC-20BB-Filter.htm (Chloramine & Chlorine Filter)
Thank you,
WaterFilters.NET