HELP done a jet wash today and the water just wont clear , this often happens and i just put my jet nozzle down the grid and it clears it but it wont clear today ,ive told her not to pay me and i will go back tomorow when water has finaly drained but soon as i finish last bit of wash it will block up again ,im woried i will loose my wage of 115 pound by having to get a pro out to do drain ,,,any help please gang a s a p thanx in advance