One of the divers is using a Shearwater dive computer. He appears to be able to put on music to listen to - no dive computer has the ability to play music; divers are expected to be paying 100% attention to their surroundings, air supply, buddy's air supply and dive buddy's location, etc. Music would be a distraction.
Divers' air is never measured in a percentage. It is always measured in pressure (psi for the US, bars for Europe etc.)
One of the divers is using a Shearwater dive computer. He appears to be able to put on music to listen to - no dive computer has the ability to play music; divers are expected to be paying 100% attention to their surroundings, air supply, buddy's air supply and dive buddy's location, etc. Music would be a distraction.
When Tina and Ben are talking at the back of the van before leaving to go to the lake, Ben holds out a cigarette to Tina. In one shot, she grabs it, then in the next shot he is seen still handing it to her, and she grabs it again.
At 28 minutes 35 seconds, when the drone was sent in the house while they waited outside, the camera operator can be seen as the "drone" approaches and passes the wall mirror.
At one point, a character incorrectly refers to a symbol as a "pentagram." It is actually the Seal of Murmur.