Aquarium puzzle

One waterline in each section

An Aquarium logic puzzle divides the glass into outlined sections. Every section has a single horizontal waterline. Water fills the cells on that row and all cells below it inside the section, including its irregular parts.

Read the numbers beside the glass

The square numbers on the right belong to the rows. The square numbers below belong to the columns. Each number counts cells containing water, rather than the height of a whole section. Watch how changing one section affects several clues.

Set and clear a water level

Tap a cell to place that section’s waterline there. Tap its current waterline again to empty the section. With a keyboard, use the arrows and Enter. The thicker internal lines mark the section boundaries; the finer lines divide the cells.

Balance rows and columns together

Aquarium puzzles have linked clues. A level that fits one row may put too much water in another column. Revise levels until every total matches. Each board here has a checked unique solution, and the glass remains vertical when the board is resized.

Play an Aquarium puzzle online

Expand the board if you want a larger view, or open the information button for its controls. The saved practice session continues in the same browser while it remains available. A connection is needed, and solving the board does not change your Edgekin island.