Planted Tank Guru
Join Date: Jan 2010
Location: Contra Costa CA
Look for Safe-T-Sorb in places like Tractor Supply, perhaps Graingers.
It is a blend of soft browns and medium grey that looks very natural, and subtle.
It will remove the carbonates from the water.
It can be used straight from the bag if you want, but be prepared to do a couple of water changes (rinsing it in the tank) or you can rinse it in buckets if you need smaller amounts. The first 2 fill-and-drains were pretty muddy, but the third fill was pretty good, and it has not clouded up when I rearranged the rocks, or did another water change.
40 lb bag filled my 5' x 16" tank barely 2" deep. After I rearranged the rocks, and they took up some space that was just fine.