Tools
CO2 calculator
Estimate dissolved CO2 from KH and pH values. Use the chart to visualize target ranges and confirm your reading.
KH + pH to CO2 ppm
Freshwater focus
Calculate dissolved CO2
Use the standard KH/pH relationship for planted freshwater aquariums.
Saltwater systems need a different CO2 approach. Use marine-specific guidelines for reef tanks.
CO2 reference chart
Cross-reference KH and pH values to compare your result with typical CO2 ranges for planted tanks.
KH (rows)pH (columns)
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