I have chloramines and I use a 6 stage filter: particulate -> BRS catalytic carbon -> ChlorPlus 10 -> 1 micron carbon block -> R.O. -> D.I. This produces 0 TDS water free of chloramines and its byproducts.
I would be concerned using water with a TDS over 2. The minute mine gets over 3, I get cyano. This is in a UNLS system with 0 nitrate and 0 phosphate. Change the filters, get it back to zero and the cyano disappears. I know your post doesn't mention a cyano problem, but ..... its a consideration.
Does the water system in the DC area treat with Chloramine? The first thing I did when I moved to Birmingham was call the local treatment plant and check if they used it and was told that they didn't. If the local water system is not dosing, you shouldn't have to worry about it.