Goofs

At 1:26 minutes and at 3:00 minutes, the chess board is set up incorrectly. Unfortunately it has been rotated 90 degrees, because the square in the right corner, must always be white.

The plants in the apartment still get watered even though all other water is turned off.

After Nemo accidentally sets the alarm off when he tries to leave the apartment, neither the security company nor the apartment building employees check to see what is wrong.

There's no way a sprinkler system is going to go off in a high rise building for a fire and be completely ignored by the building maintenance or the fire department. It's also inconceivable he didn't think of the fire alarms until weeks later. However, the alarms may have been disconnected from the system because of the heist, and he wouldn't want to risk ruining the art or getting caught until he started to get desperate to survive.

Incorrectly regarded as a mistake: early in the film Willem Dafoe remarks, "There isn't even a can opener." Later, the can opener is prominently displayed on his altar. This is a bit of humor to show that, indeed, he did eventually find the can opener.

Fire alarms are not triggered by flames but by smoke. No need to climb on the sink. He was triggering the sprinkler system with flame, not the smoke alarm.

He grows a bit of a beard, but even after seasons change, no change in his hair length or length of his beard.

Whenever Willem Dafoe is seen sketching --- whether with a marker on the framed picture or with chalk on the wall --- his stroke is not artistic at all (see the horns on the character with glasses) but when it is a close up on the hands, or when the audience sees a finished sketch or drawing, it is of much better artistic value (for example, the inner circles around the eye on the wall, compared to the outer circles); revealing that Dafoe did not draw the sketches and most of the drawings.

To help anyone in a similar situation: if you like to use a magnifying glass to set paper on fire. Do not aim for the white parts. It's the dark bits that make a difference. Good luck on survival by destroying less than Nemo did.

Nobody ever comes in to feed or check on the fish. You can't leave a fancy aquarium alone for weeks even if you have an automatic feeder.

He defecates in the bathtub, but that is a load of feces from a guy starving to death.

As the main character enters the apartment, a chess board is shown on a table with the board set up in the wrong direction.

Although the pieces are set up in the correct position to begin a game, the a1 square on the bottom left is white, whereas it should be black.

Throughout the entirety of the movie, Nemo is shown with a thin, scruffy beard.

It can be presumed through exterior clues (Fireworks during 4th of July and snow falling in likely December/January) that he is stuck in the apartment for at least 8 continuous months (April-December).

Therefore, it is impossible for his beard to not grow any thicker. Nemo is not shown on camera either shaving or finding a razor to utilize, and thus it is inconsistent for his beard to remain the exact same length for that long of a period.

The water does not go under the front door to reveal a flood in the apartment.