.5 micron carbon block filter

I bought a counter top filter to replace my brita pitcher,

http://www.amazon.com/gp/product/B0018MVZJE/?tag=skimlinks_replacement-20

and a .5 micron carbon block filter, to use instead of the included 5 micron filter.

http://www.amazon.com/gp/product/B000246SMS/?tag=skimlinks_replacement-20

So my question is, should this break down all my chloramine? Will it change my mineral profile significantly? I had the water tested by ward over 2 years ago, so I suppose I'm due to have it tested again anyway.

Mostly I just want to know if anybody has any knowledge about using a single .5 micron carbon block filter for preparing their brewing water. Previously I was just using my tap water, unfiltered, with camden tablets for the chloramine.

Yes, a carbon block filter will reduce chloramine but the amount of the reduction depends on the contact time so slower flow will result in greater reduction. To find out how effective the reduction is you can obtain a chlorine test kit from a pool, aquarium or water testing supply company. Be sure it is capable of detecting chloramine ('total chlorine'). If the reduction isn't sufficient slow the flow or put two or more filters in series.

A simple and generally effective test (unless you are one of a small number of people who can't smell chloramine) is to fill a tumbler with water, let it stand over night and then smell in the vicinity as you pour the water back and forth between two tumblers. If you can still smell chlorine then the level is probably high enough to be a problem in your brewing. If you can't, you are probably OK. See the sticky on Campden tablets.

The filter will not have an effect on iorganic ion content.

I had the PB1 the OP has, I just replaced it with the CTO+. These are the regular 9.75 x 2.5 cartridges. When I ordered the replacement, Katey at Pure Water Products included some test strips for total chlorine.

My tapwater indicated 3ppm. Both filter samples did not change colors at all, the same indication I got from the distilled water sample, less than .5 ppm according to the color key.

As my old boss would say, I don’t understand all I know about this. I know Martin has estimated the flow should be .1 gal/min or less to adsorb the chloramine. I’d like to know how he came up with this. Not disparaging, but curious.

Apparently the chloramine is WAY less reactive than free chlorine. Plenty of people are getting away with either no treatment or a quick pass through a 5 micron filter.

I have been using Campden in addition to the filter since I discovered I had chloramine, but I can’t discern any difference in taste compared to the older batches.