For water clarity, you would be better off with a micron filter pad or regular change of filter floss in your filters.
Any kind of absorbtion media, Carbon, Chempure, and even Purigen is going to help with clarity, but I think in the long run a micron filter pad would be best.
What I have seen some people do, is pack a Eheim Canister with Polishing Pads, filterfloss, and a 100 micron pad. Then run that for a day or two to polish the water.
I have used Chempure for polishing, and nitrate reduction, and it does help. It does work. Nothing beats a good waterchange though for total nitrate reduction.