I know it's been posted on here that you could get empty dropper bottles from a pharmacy. Sadly they don't hold much liquid and sometimes hard to wash after using them. Well when I was searching for some, I'm good friends with my local pharmacist (CVS), and he gave me cough medicine bottles. They hold 50ml of liquid, child proof cap and easy to wash. Just tell them that your mixing food coloring and need big bottles. I'm attaching a picture of said bottle.

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