Tub filled with marble

[mddesign]

As promised I'm back... OK, after Allen provided me with the file for the barrel vault over my tub, I've been working my heart out. My husband is a wonderful designer, but this design is a challenge for me becasue I've never done any cad / design work. I built the tub base using a custom slab and a custom counter and applied an arch to it. It's great except for one issue, the marbel in the tub, how do I get rid of it? There is no mounting options, so I'm completly perplexed. Any help would be great. Thanks
Gail
using design pro 8.08
P.S. I tried to upload a picture but it is to large.