Notes
1 lap - 45
1 lap - 47
1 lap - 50
1 lap - 51
1 lap - 52; 5 lap split = 4:05
half lap - 24 (waited a bit for scuba divers)
half lap - 24
10 straight laps:
1 - 49
2 - 52
3 - 52
4 - 53
5 - 54
6 - 55
7 - 54
8 - 54
9 - 55
10 - 54
then 4 laps (to get me to an even 20) - 3:23
then 3 sets of 5
1 - 4:22
2 - 4:28
3 - 4:30