Poolstar Pool Buffer Sodium Bicarbonate 4kg SKU: 065386 MODEL: ASG4590 Error. try again later You've successfully joined the club $ 25 .98 each Available on orders $50 to $1500. More info × Mitre 10 SAvailable at selected stores. Check your local store for details Variants Prevents rapid changes in pH levels from rainwater etc. Features and benefits Increases alkalinity of the water.