I recycle our 5 gallon spring water bottles into small plastic trays. I use them for casting resin toys to catch drips and spills. My wife uses them to sprout seeds when gardening. You can see in the photo how the seed package can be slipped in between the two stacked trays so you know what you’ve sprouted. These trays are great for organizing drawers, holding pens, pencils, snacks, and food prep in the kitchen. HDPE #2 plastic is FDA approved for use with food. That’s why water, milk, and vitamins are in HDPE plastic. It’s high quality stuff, so you might as well reuse it somehow. Reduce the plastic going into land fills, make these simple trays and use them around the house, work space, and crafts area. Carefully use a pair of tin snips or sharp scissors to cut the trays from the empty water container, and see how many uses you can come up with for these nifty stacking trays.