An ergonomic stool specimen collecting device for collecting a stool specimen during use of a toilet or commode, and for containing the collected stool specimen, the device comprising: a) a bucket for mounting on or under a seat of a commode or toilet to collect a stool sample deposited by a subject during use of the commode or toilet, the bucket having an internal volume of at least 300 ml, comprising: i) a top edge defining a top surface; ii) an interior comprising an interior side defining an interior circumferential vertical surface, and a plurality of sample disruption ridges on said interior circumferential surface distributed radially with respect to a bucket central axis; iii) an exterior having a gripping feature; and iv) a first threaded engagement portion; b) a lid having a lid central axis, the lid comprising: i) an exterior top surface comprising a gripping feature; ii) an interior top surface; iii) a mated threaded engagement portion adapted to removeably engage with said first threaded engagement portion of said bucket; iv) a floating plate seal disposed within said lid and covering the interior top surface of said lid, and configured to seal the junction between said bucket and said lid when said first threaded engagement portion of said bucket and said mated threaded engagement portion of said lid are engaged with each other, said floating plate seal comprising a floating plate comprising an upper horizontal surface comprising at least one raised feature, and a bottom horizontal surface, wherein said floating plate seal is configured to travel independently of said bucket and said lid when said lid is rotated with respect to said bucket around the lid central axis during engagement or disengagement of said first threaded engagement portion and said mated threaded engagement portion, and wherein, when said first threaded engagement portion of said bucket and said mated threaded engagement portion of said lid are engaged with each other, said upper horizontal surface of said floating plate seal is disposed toward the interior of said lid and said raised feature of the upper horizontal surface of the floating plate contacts said lid, and said bottom horizontal surface of said floating plate is essentially perpendicular to said circumferential vertical surface of said bucket. a) a bucket for mounting on or under a seat of a commode or toilet to collect a stool sample deposited by a subject during use of the commode or toilet, the bucket having an internal volume of at least 300 ml, comprising: i) a top edge defining a top surface; ii) an interior comprising an interior side defining an interior circumferential vertical surface, and a plurality of sample disruption ridges on said interior circumferential surface distributed radially with respect to a bucket central axis; iii) an exterior having a gripping feature; and iv) a first threaded engagement portion; i) a top edge defining a top surface; ii) an interior comprising an interior side defining an interior circumferential vertical surface, and a plurality of sample disruption ridges on said interior circumferential surface distributed radially with respect to a bucket central axis; iii) an exterior having a gripping feature; and iv) a first threaded engagement portion; b) a lid having a lid central axis, the lid comprising: i) an exterior top surface comprising a gripping feature; ii) an interior top surface; iii) a mated threaded engagement portion adapted to removeably engage with said first threaded engagement portion of said bucket; iv) a floating plate seal disposed within said lid and covering the interior top surface of said lid, and configured to seal the junction between said bucket and said lid when said first threaded engagement portion of said bucket and said mated threaded engagement portion of said lid are engaged with each other, said floating plate seal comprising a floating plate comprising an upper horizontal surface comprising at least one raised feature, and a bottom horizontal surface, i) an exterior top surface comprising a gripping feature; ii) an interior top surface; iii) a mated threaded engagement portion adapted to removeably engage with said first threaded engagement portion of said bucket; iv) a floating plate seal disposed within said lid and covering the interior top surface of said lid, and configured to seal the junction between said bucket and said lid when said first threaded engagement portion of said bucket and said mated threaded engagement portion of said lid are engaged with each other, said floating plate seal comprising a floating plate comprising an upper horizontal surface comprising at least one raised feature, and a bottom horizontal surface,