Megaquarium’s big free overhaul lands with an invertebrate DLC — here’s what actually changes

Why this update matters: Megaquarium gets a proper tune-up before new creatures arrive

Megaquarium is getting one of its biggest free patches yet on February 25, and Twice Circled timed it deliberately: the overhaul drops the same day as the Invertebrilliant Collection DLC. That’s not a coincidence – the studio is reshaping campaign flow, interface tools and even core resource systems to make room for a wave of spineless sea life and new tank designs.

• Campaign pacing has been reworked to avoid repetitive research and angry bottlenecks.
• UI and staff tools get meaningful upgrades – search, capacity icons, priorities and better backpacks.
• Calcium is now a required resource for some animals, turning an optional buff into a planning constraint.
• The Invertebrilliant DLC brings corals and new tank types (floor, magnifying, and wide vista) to PC – paid DLC launches alongside the free patch on Feb 25.

What Twice Circled actually changed (and why it matters)

Tweaks in patch notes can be boring, but this one is clearly aimed at smoothing the onboarding and reviving the base game for players who’ve slept on it. Director Tim Wicksteed wrote that he “went back and polished up the original base game campaign to make everything run as smoothly as possible.” Practically that means less repeated researching of animals and equipment, more animals showing up inside objectives, and adjusted research costs and prestige gates so progression feels fairer.

For new or returning players that’s the headline: fewer dead stops in the campaign where you spend twenty minutes grinding a single research node. For veterans, the tweaks should reduce tedious bookkeeping and let you get back to the satisfying parts — tank placement, filtration muffins, and oddly addictive fish happiness math.

UI and staff tools: small changes that add up

The update’s UI fixes are the kind of quality-of-life work that quietly transforms play. Enhanced search, a new tank capacity icon to predict crowding as animals age, and better priority options for staff will speed up micromanagement. Staff backpacks get buffs so restocking and tending tanks is less of a chore. Those are the exact sort of improvements that make long-running sims tolerable instead of punishing.

Calcium: from buff to hard requirement — and why that’s a big deal

Most intriguingly, calcium has been changed from a nice-to-have modifier into a hard requirement for animals that need it. That’s not just fiddly balance — it alters design decisions. Expect new resource nodes, new supply chains, and a reason to rethink tank adjacency. It also ties directly into the DLC’s focus: invertebrates and corals often need particular water chemistry, so making calcium mandatory feels like groundwork for the new creatures rather than a random difficulty spike.

Invertebrilliant Collection DLC: what’s in the tank

The Invertebrilliant Collection introduces a range of spineless lifeforms — corals and other invertebrates — plus three new tank styles: underfoot floor tanks, bulbous magnifying tanks and wide vista tanks. Those tank types aren’t just cosmetic; they change layout considerations and the visitor experience, which is a core hook of Megaquarium’s design loop: build interesting displays, keep creatures alive, and keep visitors spending money.

Why now — and what gamers should watch for

Dropping the free update alongside paid DLC is a smart move. It reduces friction for players buying the Invertebrilliant Collection — the base game now supports the new creatures with tighter campaign flow and proper systems — and it makes the expansion feel like a natural evolution rather than a bolt-on. It’s also a clear bid to re-engage lapsed players; Megaquarium has been steadily updated since its release eight years ago, and this is the kind of coordinated refresh that can bring people back.

That said, changes to core systems (like calcium requirements and research pacing) always risk shifting the balance in ways that annoy veterans. I’ll be watching community feedback after Feb 25 to see whether these edits reduce grind or simply re-gate progression in a new form.

TL;DR

Twice Circled’s February 25 update isn’t just polish — it’s a structural refresh designed to support the Invertebrilliant DLC. Campaign pacing, UI, staff tools and a meaningful calcium overhaul aim to make invertebrates feel integrated rather than tacked on. If you liked the original game’s tinkering loop, this will likely smooth the bumps; if you hated its busywork, wait for player reactions before diving into the DLC.

PC players can expect both the free update and the Invertebrilliant Collection to land on February 25. Keep an eye on patch notes and early community threads — this feels like the start of a new phase for Megaquarium, not just another content drop.