Palethistle

Palethistle is a log for tracking aquarium water changes and water parameters over time. It is built around a simple loop: record a water change, note the water parameters at that moment, and let the app show when the next change is due. The Home screen gives a summary of the most recently recorded parameters and a countdown to the next scheduled water change. The New Entry screen captures the date of the change, the percentage of water replaced, the temperature, pH, and hardness, along with free-text notes for each of those readings; if the screen is rotated while filling it in, the entered values are preserved rather than cleared. The History screen lists every recorded change and allows entries to be deleted, with a short window afterward to undo the deletion before it becomes permanent. The Chart screen draws a thirty-day trend using only entries that have not been deleted, sorted from oldest to newest, so a removed entry never shows up in the trend. The Settings screen sets the interval between water changes and the app's theme. The next-change countdown is calculated by adding the change interval from Settings to the date of the last recorded change; before any change has ever been logged, the countdown reads as not scheduled rather than showing today, since there is no prior date to calculate from. Palethistle reminds you when a water change is coming due through a local notification, and everything Palethistle records — every change, every parameter reading, every note — is stored only on the device. The app works fully offline, with no account and no server involved, so the water-change history for a tank stays private and accessible even without a connection. Palethistle is meant to sit alongside regular tank maintenance as a lightweight record of what was done and when the next change is coming.