Aquarium Water Change Dilution

How to use this tool

1. Enter the measurements and assumptions in the labeled fields.
2. Run the calculation and check the units in the output.
3. Copy or download the result.

Try this example

{"initial": 40, "replacement": 0, "percent": 25, "changes": 3}

Accuracy and scope

Ideal mixing only. Excludes new production, uptake and chemistry; not an animal-care or dosing recommendation.

Is my data uploaded?

This tool runs locally in your browser. Input and output are not sent to a processing server. Copy or download your result before leaving the page.