I did make an aquarium into a water propagation tank but after a few times gave up growing a quantity of plants in water. I made a foam core fiberglass covered with holes through which cuttings were inserted, up to 100 in one aquarium. The fiberglass could be raised or lowered or removed with the plants so the water could be changed. Light had to excluded from the water or alga would be a problem. The aquarium rested on a heating mat at 70 degrees with a HID light above. While it was nice to be able to see the roots grow it was not worth all the effort. Al

I use yogurt or sour cream cups and melt 3-5 3/4" holes in the lid with a pencil torch. Find something to cover the top of your box(maybe the lid) and cut, punch, drill or melt holes in it. If you choose to melt, be careful as to where you do it and don't hold it over anything important like bare legs. A drop of molten plastic on skin doesn't feel very good.

I have found a simple item with many uses--the plastic canvas used for cross stitching. Michael's craft store carries them..50Cents for 10 X 13" sheet. I used a piece yesterday to hold the posts of a small trellis in a glass jar for water rooting philodendrons. Easliy cut, make the piece slightly wider than the jar, cut the right size hole to hold the chopsticks in 2 places (vertically) per side, insert sticks. Also it holds stems upright when rooting several cuttings in water. Cut a piece a little larger than the top of the container, then cuts a few holes, one for each stem. The canvas makes perfect screens to prevent dirt from washing out of a pot, either in the bottom or in the side pocket of a strawberry pot.
Very handy stuff!
Johanna