Over here, every sipper gets checked at least once a week during cleaning ... before I put the tub back in the rack, I give the sipper a little "tweak" with my finger to make sure it has good flow.

Over time, you'll find far worse problems with floods using automatic watering systems ... new sippers are pretty much flood proof, but once those little blue diaphragms have some time on them, watch out.

Checking for floods is an every day chore for me.

-adam