I recommend transporting the entire props for bubble show in special protective cases. The covers are no exception.
The cases fabric is durable synthetic. Inside there's a 10-mm padding preventing shocks and leakage. Of course, the case is not completely sealed, but retains the most moisture.
Also we can sew cases to fit your specified sizes.
I keep my props in their cases. During the shows it is important that the props look aesthetically pleasing. The quality of cases complements the beauty of your act and the artist's reputation.