I hate when this happens.
95% of the time when I feed, I'll turn off the pumps, thaw my shrimp, rinse it, and squirt it in a clear tube that leads down to the shell. The shrimp float gently down (these days escorted by at least two seahorses) into the shell, where they are deposited in a nice, neat little pile for the horses and the mandarins to come munch whenever the please.
Every once in a while, though.....for no particular reason......the shrimp float down the tube, then WHOOSH away into some mysterious current to fly all over the bloody tank. Even though ALL PUMPS ARE OFF. And have been for a few minutes.
Yes, it happened tonight. Rassinfrassin.