Peacequarium

Peacequarium's whole design starts from a simple idea: a fish tank that lives on top of whatever else is on a player's screen. Resizable, always-on-top or tucked behind other windows as needed, it's a cozy idle aquarium simulator from developer GTGD, released in full on 15 December 2025 for Windows and macOS at $6.99, following an earlier public beta that some reviewers had already spent hours with before launch.

An interactive screensaver, and reviewers mean that as praise

The comparison to a screensaver comes up more than once in the review sample, and every time, it's framed as a compliment rather than a knock. One reviewer with over 16,000 minutes logged writes, "it's fun to have idle-ing on your screen when you go out or leave it idle overnight or while you're in class. It's like an interactive screensaver," specifically praising that "all the fish have clearly been drawn by hand which, as a digital artist I really appreciate and love." Another, with an extraordinary 42,000-plus minutes played, puts it even more simply: "its just a chill game. Its kinda like an interactive screensaver." A third reviewer frames its appeal in more personal terms, calling it "another good game for those going through severe depression and anxiety/panic issues," a specific and meaningful endorsement for the kind of low-pressure, ambient game Peacequarium is clearly designed to be.

A hundred fish, and a matching hundred achievements

Underneath the ambient presentation sits a real collection structure: a hundred fish split across common, rare, epic, and legendary rarity tiers, each individually upgradeable for better value and earning rate, with special glowing variants worth triple the value of their normal counterparts. Steam's achievement list mirrors that structure closely, listing 100 separate achievements, largely tied to discovering or collecting specific fish species, alongside broader milestones for treasure, gifts, and buffs. Global completion data shows a steep, expected drop-off from the easiest entries, around 87 to 89% for common early fish like the Goldfish and Zebra Fish, down to the single digits for the rarest late-game collectibles, a curve that matches a reviewer's own account of chasing "100 achievements and I'm on 93... getting there slowly." One player captures the collector's mindset the system is built for directly, asking for specific new species to be added: "I hope y'all add a Coelecanth fish to it at some point... I'd also hope for some crustaceans like lobsters and hermits."

Real, specific bugs reported by engaged players

Not every review is purely glowing, and the negative feedback in the sample is detailed rather than vague. One reviewer who clearly spent real time testing the game lists concrete issues: "FX Volume, Music Volume and Water Transparency sliders are all flipped horizontally in the Settings menu," and separately reports "insane lag/stutter/frame drops when game autosaves or applies backgrounds," a meaningful performance concern for a game meant to run continuously in the background. Another reviewer who says they played the beta at length reports a related but different complaint, a lack of in-game explanation: "i have questions like what do traits do after i put them on a fish... do fish breed how do i get more of the same type without rolling them," ultimately still recommending the game while wishing for a proper help window to fill in gaps left over from the transition out of beta. A couple of shorter reviews simply state the game wasn't a personal fit, aesthetically or mechanically, a fair outcome for any niche cozy release.

Built for both active and passive play

Peacequarium is explicit that it wants to accommodate two very different kinds of players, and its design reflects that split rather than favouring one over the other. Active players who check in regularly can trigger gold fever fish, super feed boosts, and treasure chests for larger lump-sum rewards, while passive players earn steadily every second, including while the game is closed entirely, so nobody is punished for stepping away for a day or a week. That flexibility shows up directly in reviewer habits: one player logs a modest two hours and describes it as "a side thing to do while working," while others rack up tens of thousands of minutes treating it as a constant background presence. One of the more engaged reviewers specifically praises the naming feature, "I love being able to name my fish," and asks for a handful of small quality-of-life additions, resizing only the window's height rather than its full dimensions, and a way to name the game's rarer "???" fish variants, requests that read as the kind of detailed feedback only a genuinely invested player bothers to write.

A streamer-facing layer on top of the core loop

Peacequarium's Twitch integration is a distinctive feature that separates it from most idle games in its price range: viewers watching a streamer's session can type !snail or !turtle to spawn small money-generating creatures into the tank for a minute at a time, or summon up to five auto-feeding mini submarines, small, low-friction ways for an audience to interact with a stream without derailing whatever else is happening on screen. Combined with Steam Inventory integration, which periodically grants gift boxes, fun fish traits, and unique glowing fish variants, the game builds in a steady drip of small surprises even for players who never touch the settings menu. None of the review sample specifically discusses the Twitch feature at length, which is itself worth noting, it's a nice-to-have addition rather than the reason players are recommending the game, but it's a meaningful bit of added value for anyone who streams regularly and wants a low-effort way to give their chat something extra to do.

Final verdict

Peacequarium delivers convincingly on its core promise, a genuinely calming, hand-drawn aquarium that can sit anywhere on a screen while a player does something else, and its most dedicated reviewers back that up with truly enormous playtime totals. Its reported settings bugs, autosave performance issues, and thin in-game explanations are real, specific problems rather than nitpicks, and worth knowing about before buying. For the right audience, though, one looking for exactly this kind of low-stakes, always-on companion, it's an easy, distinctive recommendation.