Sorry, but my understanding of 'massive' does not cover tubs with a width that is only about one quarter of the snake's length and about 15-20cm high. It's a bit hard to tell from the photos how long the tubs are but they don't look much longer than they are wide. In the context of a suitable habitat for adult bhps, 'tiny' is the appropriate adjective, IMO. My guess, based just on the pictures without confirming measurements, is that the cubic volume of the tub is less than one third of the MINIMUM you should be considering for an adult bhp.