I was thinking the same exact thing. I am just worried that if it were to fall over, it will spill. Until I can figure out how, I will stopper it just like you are. Thanks for the reply.
That's the problem I am not very good at anticipation, I have no children but I do not completely trust my dog or myself. I have it resting on a subwoofer that is about 12" high...maybe not a good idea I guess.
you might try a rubber cap like from a plumbing supplier say 2 5/8 inch or 2 3/4 with a clamp around it
Thanks for the information all. I will see if I can get a good seal on this.