PADI requires a 400 yd or 400 meter swim.

400 yds
under 6 min - 5 points
6 - 8 min - 4 points
8 - 10 min - 3 points
10 - 12 min - 2 points
more than 12 min - 1 point

400 meters
under 6 min, 30 sec - 5 points
6/30 - 8/40 min - 4 points
8/40 - 11 min - 3 points
11 - 13 min - 2 points
more than 13 min - 1 point