Green algae is the scourge of beaches and swimming pools. Yet so-called 'pond scum' could have a future positive role in improving crop yields. Jim Drury reports.
01:13
01:01
01:16
01:31
01:37
03:24
01:52
03:15
00:58
00:44
01:06
01:02
02:46
01:01
00:57
02:02
02:29
01:22
00:38
00:38
00:52
01:02
01:10
00:58
02:22
02:08
01:01
01:01
00:48
01:02
01:24
03:00
01:41
01:54
01:20
02:24
01:02
01:10
01:20
01:20
01:13
03:17
01:54
00:57
01:51
00:41
00:42
00:31
01:09
01:17
01:18
01:23
01:01
01:49
01:08
02:08
00:59
01:07
00:54
01:36
01:05
02:14
04:48
02:03
01:12
01:16
00:48
00:59
02:10
01:17
01:10
01:15
01:35
02:10
02:03
05:12
01:28
01:02
01:12
01:06
01:01
01:31
01:37
03:24
01:52
03:15
00:58
00:44
01:01
02:46
02:02
02:29
01:22
00:38
00:38
01:16
03:10
01:05
01:31
00:46
01:29
00:52
02:00
02:00
01:04
01:19
00:47
01:26
01:13
01:22
01:28
01:28
01:22
01:15
01:20
01:33
01:48
02:33
03:40
01:05