The position of the buoys, therefore, the height of the platform is operated with {HEAD ~ the level} of the mixture in {TAIL ~ the first tank} 
The position of the buoys , therefore , the height of the platform is operated with { HEAD ~ the level } of the mixture in { TAIL ~ the first tank }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL