Smart Turtle Tank: Build a DIY Camera, Water Sensor and Monitoring Setup for Your Turtle

Smart Turtle Tank is the write-up of the monitoring setup I built for my baby turtle, Bobuerto: a turtle cam, a water sensor and a 3D-printed enclosure, written as a plain first-person maker guide for people who have never held a jumper wire.

The water sensor is a Seeed XIAO ESP32-C3 reading three cheap probes (temperature, TDS and turbidity) with no soldering. The wiring chapter goes one sensor at a time, one wire at a time, with a checkbox for each wire and a diagram for each sensor. The camera is an ESP32-CAM posting to a Cloudflare Worker on the free tier, with an installable web app, an AI health check every 15 minutes and push alerts.

Then the firmware outline with every code block explained line by line, the server side (storage, calibration maths, alert rules), an ESPHome and Home Assistant route, the printed box, hook and hanger (and the two prints that failed), and the turtle care numbers the whole thing watches: water temperature, basking, UVB, filtration.

What you get

• A three-probe water sensor wired with no soldering: one sensor per page, numbered steps with checkboxes, a diagram for every sensor, and the power-up check that catches mistakes before you plug in
• The one dangerous wire explained: why the turbidity signal needs a voltage divider before a 3.3 V pin, with the schematic and the numbers
• Firmware you can read: median filtering, rejecting the temperature probe's fake readings, an offline buffer, a watchdog and a 5-minute HTTPS POST, line by line
• A turtle cam on a free tier: ESP32-CAM to Cloudflare Worker, passwordless login, an AI health check and push alerts, with the daily budget worked out
• Turtle care the sensors are built around: temperature bands, basking and UVB rules, filtration and water changes, and what TDS and turbidity do and do not tell you

59 pages, 26 figures, a troubleshooting flowchart, a glossary and a one-page cheat sheet. PDF and EPUB. Homelab the Right Way, Book 4.