I got something similar from Amazon only they were small plastic containers with a screw on top. I eventually grew out of them (like the next day) and I couldn't justify having 20 corn containers because they only fit a few kernals each. This is a great set up but I'll share what I use in case you grow out of these:

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Started very similar to you: First Container

Had to move to this: Bigger!

With baggies instead of hard plastic containers