To make cuttings, I like to use 12V ultrasonic nebulizers with 45mm diameter.
These work most efficiently about 3 centimeters below the water surface. So I designed a raft that achieves exactly that.
If you want to recreate the project, you'll also need some styrofoam or pool noodle so the raft floats and can carry the nebulizer. That's it!
Have fun with it.