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Substrate Calc

Privacy policy

Privacy policy

Last updated 2026.

Aquarium Substrate Calculator is a static website. The calculators run entirely inside your browser, which shapes what we can and cannot collect. This page explains it in plain language.

Information we do not collect

  • No accounts, so no names, email addresses or passwords are stored.
  • No analytics, advertising or tracking cookies are set by this site.
  • No measurement you enter — tank size, depth, material — ever leaves your device.
  • No payment details, because nothing is sold here.

Information that is processed

When your browser requests a page, our hosting provider records standard server log data such as IP address, user agent, the page requested and the time of the request. This is used for security, abuse prevention and aggregate traffic reporting, and is retained only for as long as the host needs it.

If you send us a message through the contact form, it is handed to your own email application rather than posted to a server on this site. We receive only what you choose to write, and we use it to reply and nothing else.

Local browser storage

The calculators write your current inputs into the address bar as query parameters so a result can be shared or bookmarked. That is stored in the URL history of your browser, not on our servers. Clearing your history removes it.

Third-party services

Typefaces are served from Google Fonts, which receives your IP address when the stylesheet loads. Google Fonts is a third party with its own privacy policy. We do not embed video, advertising networks, social media pixels or comment widgets.

Your rights

Because we hold no personal records on this site, there is generally nothing to access or delete. If you have emailed us and would like your message removed from our inbox, write tohello@aquariumsubstratecalculator.com and we will confirm once it is gone.

Changes to this policy

If the site ever gains analytics, accounts or a server-side contact form, this page will be updated before those features go live. The revision date at the top always reflects the current version.