For reference a bladder may be a pillow tank but a bladder may or may not be self supporting. The capacity of the pillow tank with It can be self supporting style and design holds about 70% of what a rectangle would. IPI has worked with tank factories for nearly https://www.facebook.com/permalink.php?story_fbid=pfbid02UofXeQ6DfCYy65BHff9tznWhzErifF8cTQ1GtUwU6gJPhQC9yWnecKsbvi9DbVFnl&id=61560512640678&__cft__[0]=AZV3aSsv0b-UqCYoTL8TT8O5DvILAdotOBft4YGXYWvmAnGWefqKMKk6XZI99olfH4DcQoLGqSGC0NkrLTBzQ1mZvVKtp9qsY8rRmt5NMuAYx5LFpCgysvHbyrNMUyYPY9govG4Cmv8eiouHTGLXVakHVEy8Oq6HvrTk4wr-CfAGr0PFUMF1U02SAXZQMdoxDRUzkRTJYbcaayBmY95Wg9M0&__tn__=%2CO%2CP-R