These are the little food jars in the video. I use this to feed smaller portions to the Sea Monkeys in Mars. Unfortunately they sell them in a box of 10. I only needed 2 and put a half packet of food in each. But I find them very handy.
One shake is about 1/16 of the yellow measuring spoon. (I did a few basic tests and it took 15 to 18 shakes to fill the spoon level. ) Not exact but easy to use.