A phosphate/carbonate free buffer for lowering and stabilizing pH in the acid range of pH 4–6.8. Acid Buffer™ is designed primarily for freshwater use, is ideal for planted aquaria, and may be substituted for Discus Buffer™ wherever phosphate buffers may pose a problem, such as in high calcium waters or aquaria prone to undesirable algae growth. It is compatible with Discus Buffer™, Neutral Regulator™, and Alkaline Buffer™. It may be used to safely lower pH in marine water. A 250 g bottle treats 800 gallons.