... ideal range. Prevents water from becoming corrosive and damaging pool’s plumbing and heater. Stops staining and etching of pool surfaces caused by low ... (or 2lb),2kg (or 5lb),3kg,4kg (or 10lb),8kg and 10kg of Pillow Bags, Doy Packs,Gusseted Bags.0.5kg ... (or 2lb), 2kg (or 5lb), 3kg, 4kg (or 10lb), 8kg and 10kg of Pails, Jars, Jugs, Pots, Tubes, Drums ...