About
About Dial-In CO2
A free calculator for planted-aquarium hobbyists.
What this site is
Dial-In CO2 is a free tool that turns a pH reading and a KH test into an estimated CO2 concentration, a starting bubble rate, and guidance on reading a drop checker. It's built for planted-aquarium hobbyists who want an honest, calculator-backed starting point for CO2 dosing rather than guesswork.
Why it exists
The pH/KH/CO2 relationship is simple math, but the numbers involved are easy to get wrong by hand, and small mistakes compound quickly since the relationship is exponential. This site exists to make that calculation fast, repeatable, and free, alongside plain-language guides on the measurement and troubleshooting details that the calculator alone can't cover.
Who runs it
Dial-In CO2 is an independently run site, maintained by a single person. It isn't affiliated with any aquarium equipment brand or manufacturer.
Get in touch
Questions, corrections, or feedback are welcome at [email protected].