Water sort puzzle for beginners
A water sort puzzle (also called a color sort or liquid sort puzzle) looks like a toy and plays like a small logic problem. This guide takes you from the first pour to a board you can plan, in plain steps. The examples use Decant’s rules: four units to a tube, two spare tubes, no timer.
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The goal, and the only three rules
You start with tubes (jars, bottles, vessels: the name changes, the idea does not) full of mixed colors. You win when every tube is either empty or holds a single color. Three rules do all the work.
1. Pour onto a match
You can pour the top color of one tube onto a tube whose top is the same color, as long as it has room.
2. Or into empty
An empty tube takes any color. In Decant every board is dealt with exactly two empty tubes, and that never changes.
3. The whole top run moves
If three of the same color sit on top, all three pour together, or as many as the target has room for.
Four to a tube
A tube holds four units and each color has four units, so a finished tube is always exactly full. Finished tubes lock.
A first board, pour by pour
Here is the smallest board that still teaches the idea: two colors, red (R) and blue (B), in four tubes. Read each tube from the bottom up, so the last letter is the top.
| Pour | Tube 1 | Tube 2 | Tube 3 | Tube 4 |
|---|---|---|---|---|
| Start | R B R B | B R B R | empty | empty |
| 1 → 3 | R B R | B R B R | B | empty |
| 2 → 4 | R B R | B R B | B | R |
| 1 → 4 | R B | B R B | B | R R |
| 2 → 3 | R B | B R | B B | R R |
| 1 → 3 | R | B R | B B B | R R |
| 2 → 1 | R R | B | B B B | R R |
| 2 → 3 | R R | empty | B B B B | R R |
| 4 → 1 | R R R R | empty | B B B B | empty |
Notice what the two spare tubes did. The first two pours spent them to uncover colors that could then pour onto a match. After that, every pour was onto a matching top, and the board emptied itself. That rhythm (spend a spare to uncover, then stack on matches) is the whole game in miniature. Real boards have five to ten colors, but the loop is the same.
Five habits that beat most boards
Adopt these in order. Each one fixes a mistake the previous one leaves open.
- 01Read every top before you pour.Look along the row of tubes and name the top color of each one. The legal pours are only ever between equal tops or into an empty tube, so this short scan lists your real options and stops you pouring on a hunch.
- 02Match before you use empty.A pour onto a matching top costs no spare room. A pour into an empty tube spends some. If both are available, start with the match, especially when it empties a tube and hands you a spare back.
- 03Know your spare count.Say it out loud: “I have two empties.” Every mixed pour into an empty tube takes one away. Aim to keep one empty tube in reserve for as long as you can, and spend the last one only when the pour clearly frees something.
- 04Pick a target color, not a target pour.Choose the color closest to finished, the one with most units already near the tops, and ask what has to move so the rest of it can reach the surface. Then work backward from that.
- 05Look one pour ahead at what you uncover.Every pour reveals the color under the one you moved. If the revealed color has nowhere to go, the pour only used up room. If it lands on a matching top, you made progress.
The mistakes beginners make
- APouring a color onto a different color’s tube “to get it out of the way.”You cannot, because pours only land on matching tops or empties. What looks like a plan is usually a misread top. Name the tops again.
- BUsing the empties first.It feels productive and it is the fastest way to run out of room. Try the matches first.
- CSplitting a run.If your run of three has room for only one in the target, one moves and two stay behind, and now the color is in two places. Wait until the run fits, or make room first.
- DPouring back and forth.Moving a color between two tubes and back changes nothing. If you notice it, undo to the last real decision. Decant gives free players three undos per board.
If you do pour yourself into a corner, the deal is not at fault. Every Decant board is proved solvable before you get it, so a stuck board is always about the order of pours. How to spot that early is covered in dead ends and hard boards.
Playing it calm
A sorting puzzle is at its best when nobody is hurrying you. Decant has no ads and no timers, and nothing is sold that changes the rules: no lives, no energy, and no extra tubes. A lost unranked board restarts straight away for free, so you can treat a bad line as information rather than a penalty. For a relaxing puzzle that fits a few spare minutes, that is the point.
Decant is free to start: the tutorial, today’s Daily and the first 30 of its 180 boards. A one-time unlock (or a StackForge Play Pass) opens the rest. Neither tier changes the rules or the number of spare tubes.