I have a messy container that I keep all my aquarium tests in. The Hanna boxes take up a ton of space, and don't seal the reagents (Hanna says they go bad after the package is opened). They also don't leave the cuvettes or lids in a good air drying place.

To get rid of the plastic bags I've been keeping it in, I spent way more time designing and printing these Hanna tester containers than I'd like to admit. The reagents are kept in a little container, all the cuvettes and lids are held upside down in ventilated areas, and screwed in so they don't bounce around. They are small, the base is reusable across testers, and the top piece can be swapped for different types. You can see through the front to grab the right test (I might make that little lid have the test type name in it).

There are many others of these, but I wanted to build this one to ensure things were stored upside down (to drain), highly ventilated, things locked into place, and individual tests separated versus a big multi-device holder.

This was designed to not require supports, and the profile I provided does not include them.