Boyd's Chemi-pure

Chemi-pure can be used with all water types as a chemical absorption filter and ion generator and exchange unit to positively keep pH at a perfect constant level. Also fantastic for use with African Cichlids and Discus! Needs replacement only every six months under normal circumstances. Use 1 unit up to 40 gallons, 2 units from 40 to 100 gallons, above 100 gallons add one unit for every 25 gals. 10oz