 The 9 @,@ <unk> @-@ square @-@ foot ( <unk> @.@ 4 m2 ) pool used 3 by 3 feet ( 0 @.@ 91 by 0 @.@ 91 m ) pavers that weigh 250 pounds ( 110 kg ) . The pavers were rested on screw jack <unk> in order to be leveled and <unk> . The pavers had to be perfectly leveled for the water to work correctly because the fountain incorporates numerous sensors to regulate the flow and level of the water . 
