For Athena and Melody ionizers.
Use in Filter Position 2 on the Athena or as the only filter in the older Melody.
The BioStone Plus starts with the same compressed carbon block as the Basic, then we add Plus technology by impregnating it with specialty media to increase contaminant reduction.
It removes more Chloramine, heavy metals and other tough contaminants than the BioStone Basic, but not as many as the Ultrawater filter.
Containing Scale Guard protection, it will out perform any GAC filter – regardless of micron rating. (Rated for 1000 gals.)