use an plate for tides attached with long vertical bar,link bar with bicycle chain, and attach cycle bearing to it, it will be purely success

hi u could use double layered method, where no purification is done and the water is stored in underground layers, but it slight costly intially but once we make it...

if u would like to i will give an new way of working mechanism submarine, and i think it helps u more or else in simple means of our own...