I’ve mentioned it in the weekly thread but these are sitting an inch deep in nutrients and water. They drink it down, and I refill it when they need it. Its a hydroponic method called kratky. I don’t have a hose or a lot of room so this might be a good solution for me. Excited to see how it goes!
2/3 of the container height is generally a good ballpark. You can also check where the air roots start and just stick to height lower than that.