水球球是一個多孔噴泉，孩子們愛和水球球互動的方式是去堵住出水的小孔，或者整個身體撲上去。堵住他們所能覆蓋的孔洞，觸碰水的壓力。Hedgehog Spray is a porous fountain. Childrens favorite ways to interact with the water hedgehog is to plug the holes with hands or  with their whole bodies.  Throught pluging,  children can feel  the pressure of  water.