KH Buffer Powder for all Marine Fish and Reef Aquaria Overview Highly-effective alkalinity-increasing (”buffer”) powdered blend. Helps increase pH stability in an aquarium by raising the alkalinity; continued addition raises pH until 8.3 is reached, at which point the pH remains unchanged and the alkalinity alone increases. Provides a source of carbonates, which make up the majority by weight of aragonite, the mineral secreted by reef-building organisms as skeletal material. Formulated by a marine scientist. Determine alkalinity in aquarium with an accurate test kit prior to supplementing. Do not add this product directly to an aquarium without first diluting in water as directed