Water Sort is a gentle colour puzzle. A row of glass tubes holds stacked bands of coloured liquid, all mixed up. Pour from one tube to another until every tube holds just one colour. There’s no timer and nothing falls — just you, a few empty tubes and a plan. Early levels take seconds; later ones, with a dozen colours, can take some careful thought.
How to play
With a mouse or finger, tap a tube to pick it up. It lifts slightly so you know it’s selected. Then tap the tube you want to pour into. You can also drag straight from one tube to the other. Tap a lifted tube again to put it down.
On a keyboard, use the left and right arrow keys to move between tubes, or press 1–9 and 0 to jump to the first ten. Space or Enter picks up the chosen tube, or pours into it if one is already lifted. Escape puts it down, U undoes, H shows a hint and R restarts the level.
Undo, Hint, Restart and Symbols sit under the tubes. The bar at the top shows the level, your moves against par, and the highest level you’ve cleared. New gives you a fresh random board with the same number of colours.
Rules
- Each tube holds up to four layers.
- You can pour the top colour of one tube into another only if the target is empty or its top layer is the same colour.
- All the matching layers on top move together, as many as there is room for.
- You win when every tube is either empty or full of a single colour.
- If no pour is possible, the board is stuck. Undo or restart to carry on.
- Your rating is your move count against par. Undos count as moves.
Strategy
Use empty tubes as workspace, not storage. An empty tube is the most useful thing on the board. Fill one only when it gets a colour started, and try to finish that colour quickly.
Look for nearly finished colours. If three of a colour are already on top of different tubes, gathering them into one place frees space fast.
Dig out buried colours. A colour stuck at the bottom of a tall tube needs everything above it moved. Plan where those layers will go before you start.
Don’t split a run. Pouring only part of a stack (because the target is nearly full) leaves the same colour in two places. Sometimes it’s necessary, but it usually costs extra moves later.
Think two pours ahead. Before each pour, ask what the next one will be. If the answer is “nothing useful”, pick a different pour.
Use hints to learn. A hint shows a pour that still leads to a solution. If it says there’s no way out, undo a few steps rather than restarting.
History
Sorting puzzles have a long history, from coin and ball sorting games to the “liquid layers” demonstration in school chemistry. Pouring liquid between containers with fixed capacity also echoes the classic water jug riddles that date back centuries. The modern tube-sorting format became popular on phones around 2020 as a quick, relaxing puzzle, with many versions using balls, liquids or sand. Water Sort is ArcadeWren’s own version, with its own flask design, a colour-blind symbol mode and levels checked by a solver.
Variants
- Par hunting. Replay levels until you clear them at or under par.
- No-hint runs. Play a stretch of levels without a single hint or undo.
- Symbols only. Turn on Symbols and try sorting by shape rather than colour.
- Bigger tubes. Versions with five or six layers per tube, which ArcadeWren may add later.
Frequently asked questions
Is Water Sort free to play?
Yes. It runs in your browser on desktop, tablet and phone with no download or account. Your level and settings are saved on your device.
Is every level solvable?
Yes. Each board is checked by a solver before you see it, and boards it can't finish are thrown away. You can still get yourself stuck with the wrong pours, but Undo and Restart always get you back.
What does par mean?
Par is the number of pours the solver used to clear the board. Finish at or under par for three stars, a little over for two, and anything else for one. Undos count as moves.
How do I pour on a phone?
Tap the tube you want to pour from — it lifts up — then tap the tube you want to pour into. You can also slide your finger from one tube to the other.
Why won't a pour work?
You can only pour onto the same colour or into an empty tube, and only while there's room. If the target can't take it, tapping it picks that tube up instead.
I can't tell some colours apart. What can I do?
Turn on Symbols. Every colour then carries its own small shape, such as a circle, square or triangle, so you can sort by shape alone.
What do Hint and Undo do?
Hint lights up a pour that still leads to a solution, or tells you if there's no way out from where you are. Undo takes back your last pour.
Do the levels get harder?
Yes. Level 1 starts with three colours, and every three levels add another, up to twelve colours and fourteen tubes. After that, levels stay at twelve colours but every board is different.
Last updated by the ArcadeWren team.