Aquarium
Hard
00:00
Classic
Hard Aquarium — what to expect
Hard Aquarium stays on medium’s 8×8 grid but packs in 8 to 11 aquariums, some of them irregularly shaped — the step up is the thinking, not the size. Over/under counting becomes a real technique: before committing to a water level, check whether that level would push any shared row or column past its target. Several aquariums will have multiple plausible levels, and you need to find the one that satisfies all constraints simultaneously.
How to play Aquarium
- The grid is divided into tanks. Pour water into them.
- Water settles level: inside one tank it fills from the bottom up, never leaving a gap.
- So if a cell holds water, every cell of that tank below it holds water too.
- The number beside each row and above each column counts its filled cells.
- A 0 means that line stays completely dry. A number equal to the line length means it all fills.
- Every puzzle has one solution, reachable by logic alone.