Aquarium Days is a casual single-player game centered on collecting and observing fish in customizable aquariums. Players build peaceful underwater displays on PC, choosing from dozens of species that behave according to their natural patterns while earning resources even when the game runs in the background.
Gameplay
The core loop revolves around acquiring new fish and arranging them in aquariums that reflect different environments. Sixty species appear across 117 distinct color and pattern variations, including guppies, danios, corydoras, bettas, discus, arowanas, koi, and freshwater stingrays. Each species exhibits unique swimming habits, such as schooling together, lingering near the surface, or staying close to the bottom of the tank.
New fish automatically register in a built-in catalog that tracks collected species and appearances. This system encourages steady progress toward completing the full set without requiring constant attention. Equipment upgrades expand tank capacity, boost offline coin earnings, and grant access to additional aquariums. Each tank supports its own scene selection and fish population, allowing players to maintain several independent displays at once.
Feeding occurs at the player's discretion. Fish remain healthy without regular intervention, and the game imposes no water chemistry management or health concerns. Coins continue to accumulate while the application stays closed, supporting a low-pressure pace suited to short or infrequent sessions.
Game Modes
Aquarium Days operates as a single-player collection and observation experience with no separate competitive or narrative modes. The primary activity involves expanding the fish catalog through gradual acquisition and placement across multiple tanks. Scene selection serves as the main customization layer, instantly altering the visual layout of any aquarium with options that include aquatic plants, driftwood, caves, stone steps, and underwater ruins.
Desktop integration functions as an ongoing passive element. The game can run in a compact window overlaid on the desktop or function as an animated wallpaper, letting the aquariums continue their activity during other computer tasks. This setup reinforces the relaxed, always-available nature of the experience rather than structured play sessions.
Collection and Catalog System
The catalog provides a clear record of progress, highlighting missing species and appearances so players can focus efforts efficiently. Different movement patterns among fish add visual variety to each tank, rewarding thoughtful placement that showcases natural behaviors. Upgrades tie directly into collection goals by increasing space for more fish and improving resource generation during offline periods.
Desktop and Wallpaper Features
Players can minimize the game to a small persistent window or apply it as a full animated background. Both options keep the aquariums visible and active without interrupting other work. Multiple aquariums remain available simultaneously, each with independent scene and fish choices, so the desktop can display several distinct environments at once.
Is It Worth Playing?
Aquarium Days targets players who enjoy calm, low-maintenance casual experiences focused on collection and visual relaxation. The absence of daily chores, sickness mechanics, or required upkeep makes it suitable for those who want to enjoy fish displays on their own schedule. Offline coin earnings and desktop integration further support intermittent play without loss of progress. As an upcoming title planned for release in Q4 2026 with no user reviews available yet, its appeal rests on the verified features of species variety, scene customization, and passive operation. Those seeking a straightforward, pressure-free aquarium simulator on PC will find the described systems align with that preference.