Seachem Purigen 100mL Bagged 
 
Premium synthetic adsorbent, not a mixture of ion exchangers or adsorbents, but a unique macro-porous synthetic polymer that removes soluble and insoluble impurities from water at a rate and capacity that exceeds all others by over 500%
 
For freshwater & saltwater aquariums
Controls ammonia, nitrites, nitrates
Impact on trace elements is minimal
Polishes water
Prepackaged in a bag
Darkens progressively as it exhausts