Be aware that when using carbon to remove chlorine, it has some drawbacks. One, the dwell time of the water on the carbon will determine how efficient it is. If you push a lot of water through the filters very fast, you won't be removing very much chlorine. Also, unless the filter has some sort of indicator, it may be difficult to tell when the carbon has been used up and is in need of a change out.
Personally, I use an under-sink RO system to do my water refills, and I still use a de-chlor product. I don't think that much chlorine gets to my RO membrane, or the membrane would be ruined pretty quickly. But I still wouldn't want to take any chances on killing off my tank bacteria.
Just a thought.