<a href=showthread.php?s=&postid=13857781#post13857781 target=_blank>Originally posted</a> by skey44
do you have a reason for using the bulkhead instead of rigid tubing through the cap?
I used sterilite containers for cereal obtained @ target. matched very closely drill bit with 3/8" (i think, just the size that air tubing will slide over tightly) rigid tubing (to reach close to the bottom and eliminate the possibility of the silicone slipping out), length to bottom of container and hooked up silicone air tubing directly to the rigid.
the rigid fit tightly into the drilled hole in the top of container but to make it permanent i used a bead of superglue gel around the junction on both sides.
cherry corals is popping out some really nice acrylic versions of this, but I just copycatted to save the jingle for livestock.
just another way of doing it.