It's a fun thing to make. It creates small bubbles on a water jug.
No any other property added to the water implied, or expected.
You insert the magnets into the isolating piece, flat side up, on the central case, and as you plug the magnets, on the correct order, see halbach.jpg, you move the central part one magnet at a time,on the isolating piece, see the Instructions picture.
Otherwise it's very hard to insert the magnets.
Better print the central part 45º, on it's edge, on the central case, and straight up, on the isolating piece.