The problem is most likely the air pocket formed by the lip of the lid where the lid is closest to the build platform. To see the problem area better move the slice view slider down until all you see is supports. Now slowly move the slider up till you start getting to the object. Move it up a little more and you will see an area where there is an unprinted area completely surrounded by printed material. Since this area does not have a hole letting the pressure equalize during the peel and return process the pressure blows one out of one of the printed walls this leaves a hole in your print and cured material floating around your tank.
The fix is to either orient your part to prevent this or put an extra hole in the part to allow for the pressure to regulate.