I recently took apart & cleaned all the parts to my whirlpool salt brine filter. It has a canister in it that looks like an oxygen tank. It was clogged up pretty good so I emptied it out. It has some type of filter material in the tank that looks like tiny beads that are coffee colored. Can anyone tell me what the material is and how much to replace in that canister? Thanks in advance. It is a Whirlpool Model WHES30 and looks like some type of carbon resin.