When Sandy is swimming underwater with Flipper after being knocked off the dock while working, his watch and armbands flip hands during one scene with his watch on the right wrist and armbands on the left.
While on board the Reliable searching for toxic waste (potentially for three days), each person's clothing changes at least three times, but Sandy's shirt changes seven times among four different shirts: a Smashing Pumpkins shirt, a DINK shirt, a stag head shirt, and a solid gray shirt.
When the boat is bearing down on the boy near the signal marker, the tracking radar shows it ahead of the boat but off to the right, at about the one o'clock position. As they close in on it, the distance on the radar gets shorter but it stays at the one-o'clock position. If they were heading straight toward it, it would be at the twelve o'clock position.