My idea won't work in a 150 gallon tub , maybe in 300 gallon , we'll see?  Just for now cut a slice of cork added to the 2' XL zoo med dock . Will have to do until I can build the obstacle course I want .
Yesterday afternoon went to Nature Center Doc let me pick a new friend out  ,as long as it was under 6".  As a swap for Mickey.  It's a Boy , no name yet  he'll let me know that later.  Left foot has a broken claw but  not bad.  Shell needs some TLC but again nothing I can't fix.  Now Ellen... that's another issue !  Turtle will stay.
Sorry don't  know how to make a movie , both videos total only 2 minutes.   Got last night when he though he was alone.   
https://youtu.be/rRopUZbYcC0https://youtu.be/SpwYdA1FCu4