Privacy

Effective 27 October 2026.

This website

• It sets no cookies and runs no analytics or advertising.
• Its font is served from this site, so loading a page contacts no one else. Our web host, currently GoDaddy, keeps ordinary server logs.

The newsletter

• If you sign up, Buttondown, which runs the list for us, keeps your email address, when you signed up, and the IP address and page you signed up from.
• You confirm by email before anything is sent, and every email has a one-click unsubscribe link.
• We send launch news and the introductory price. We do not share the list.

The display

ReefGauge reads your controller and your Red Sea equipment over your own network, and keeps your readings, tests, photos and settings on the display itself. These are what leave it:

• Registration. During setup the display sends us:
  • your first and last name, email and phone number
  • the tank's name
  • the display's serial number, unit ID and software version
  They go to our own server (relay.reefgauge.com, hosted by DigitalOcean), with a backup copy on our office computer. We use them for support, warranty and safety notices about your display. We do not add you to the newsletter.
• Weather. The display sends the location you set (as map coordinates) to Open-Meteo for the forecast. When you search for your town during setup, the search text goes to Open-Meteo too.
• Fish stores, on the Raspberry Pi version. When you open Fish stores, the display sends the location you set to our server. Our server looks up shops near you through Google, using that location rounded to about 5 km, and keeps the list for a week.
• Software updates. Every few hours the display checks for a newer version.
  • The Android tablet asks our server and downloads updates from it.
  • The Raspberry Pi version checks and downloads from GitHub, which hosts our release files. When it installs an update, it also fetches software packages from the public npm and Python package registries.
  These requests carry the display's IP address and the release channel it follows, not your name or your readings.
• Checking for the internet. The display checks it can reach the internet using a standard Google address, the same check phones and computers make.
• Fonts. The display and the pages your phone opens from it carry their own fonts. (Raspberry Pi software from before October 2026 loaded one from Google Fonts, so Google saw the display's or the phone's IP address; updating removes that.)
• Remote support, only when you start it. A support session opens only when you choose it on the screen and give us the code. While it is open:
  • We can see the display's status, settings, current readings and recent log.
  • We can change its settings, restart it or install a software update. The display lists any settings we change.
  • We may use Claude, an AI assistant made by Anthropic, to read the display's status and log and suggest a fix. Claude is not given your name, email or phone.
  Our server notes when a session opens. The session ends when you close it, or an hour after it starts.
• Phone alerts, on the Raspberry Pi version, only if you turn them on. Alert messages, including the reading that set them off, travel to your phone through ntfy.sh.
• The ReefGauge phone app, only if you link it. Linking happens when you type the code from the display's Settings › Phone app into the app. From then on:
  • The display keeps a connection to our server (relay.reefgauge.com, hosted by DigitalOcean) and sends it its latest readings and any alarms, about once a minute and whenever they change. The server keeps only the latest set, replacing it each time.
  • When your phone asks for a chart, a log or a setting, the request and the display's answer pass through our server. We do not keep them. The phone can reach readings, logging and your own settings, never setup, support, updates or a reset.
  • Your account is your email address, the displays it is linked to, and a token for each phone so we can send it notifications. We email your sign-in codes through Resend.
  • Alarms and dose reminders reach your phone through Google's Firebase Cloud Messaging (and, on iPhone, Apple's push service). A notification carries the tank's name and the alarm or the doses, including the reading that set an alarm off.
  Turning the phone app off in the display's settings ends the connection; unlinking all phones there also removes the display from every account.
• Your phone, on your own network. Backups, photos and lab results you send from the display's own phone pages move between the display and your phone over your own network. They do not come to us.

Email to us

Mail to admin@reefgauge.com is held by Microsoft 365, which hosts our mailbox.

Who else sees it

No one buys or rents your information from us, ever.

• Your registration details. When the display tells you these are kept confidential and never disclosed outside ReefGauge, this is what that means:
  • They go only to our own server, hosted for us by DigitalOcean, and to our office computer.
  • If you write to us, they are also in our mailbox at Microsoft.
  • Those providers act for us and may not use them for anything else.
• Services that run parts of ReefGauge for us: DigitalOcean (our server), Resend (sign-in codes for the phone app), Buttondown (the newsletter), Microsoft (our mailbox), GoDaddy (this website) and GitHub (the Raspberry Pi version's updates).
• Independent services the display or the site talk to, under their own privacy policies:
  • Open-Meteo (weather and town search)
  • Google (the internet check, fish-store search, and phone-app notifications through Firebase)
  • Apple (phone-app notifications on iPhone)
  • the npm and Python package registries (Raspberry Pi updates)
  • ntfy.sh (phone alerts, only if you turn them on)
  • Anthropic (Claude, during a support session)
  They see only what is listed above for each.
• The law. We will disclose information if the law requires it.

How long we keep it, and your choices

• Registration details. We keep these while you use the display and for as long as we support it.
• Newsletter address. We keep this until you unsubscribe.
• Phone app account. We keep your email address and links until you ask us to delete them. A display's latest readings are replaced every minute while it is linked.
• Changes and deletion. To see, correct or delete what we hold about you, email admin@reefgauge.com. We will do it, normally within 30 days.
• Do Not Track. We do not track you across other sites, so a browser's Do Not Track setting changes nothing here.
• Children. ReefGauge is not aimed at children under 13, and we do not knowingly collect their information.

Changes

If this policy changes, the new version will be posted here with a new effective date.