Tideglass

Care for a small aquarium whose residents and instruments slowly reveal impossible depth.

Tideglass is a compact aquarium simulation designed to live entirely inside the extension popup. Feed the residents, change water, manage the light and filter, and watch temperature, oxygen, pH, algae, food, water level, and individual fish behavior evolve over time. The tank begins as a calm care game. As routine observations accumulate, instruments become available for discrepancies that should not exist. A depth probe can continue beyond the visible glass. Acoustic returns can appear below the apparent bottom. Fish may leave the visible water column while telemetry still reports them moving deeper. Pressure, measured volume, and reflections can stop matching the dimensions in front of you. The unusual events are part of the local game simulation. Tideglass does not use web content, browsing history, external accounts, remote servers, analytics, or downloaded game logic. Progress is stored locally in the extension page with localStorage so the tank can continue between popup sessions.