From my limited knowledge[0], it does not seem like this would be an easy structure to scan for inspection. Acrylic can even used for the wedges that interface between the phased array (or single element) probe [1] because it's very good at not interfering with ultrasounds. Water is also a very good "coupling" material, which makes it even harder to get a useful scan since there would be no "backwall" reflecting back the ultrasounds on the other side of the acrylic.

There are other ways to scan for defects, but I'm mostly familiar with ultrasound phased arrays. Other NDT methods are also hard to use in the field after manufacturing.

[0] I work in NDT (non destructive testing), but I'm not a physics engineer and (work further up the stack from the actual probes/scanners). So this is an approximation, and I might be wrong.

[1] This random link is pretty useful to get an idea I think, but I'll also ask around our inhouse scientists if I get the occasion today!

https://www.olympus-ims.com/en/ndt-tutorials/transducers/pha...