I have a 24ft A/G pool with a Hayward 100lb sand filter have had no problems last several years until yesterday,I put in my auto vacume watched it run. few min and went in the house,about 30 min later I went to check on the progress and found the hose to the vacume had disconnected from the skimmer and the skimmer was running without the basket of course because the vacume was directly placed in it,i also noticed my water had white foam all over the pool,when I shut off the pool pump the water from the pump came back up though the skimmer.i placed the basket back in the skimmer,backwashed,then rinsed and when I shut off the motor the water came back up through the skimmer again and pushed up the basket,my question is how can I stop the water from backing up from the skimmer when I shut of the motor and it is still foaming the water while the filter runs,I guess when the vacume hose disconnected from the skimmer it caused all these problems,if anyone can help I really would appreciate it,also my water levels were all balanced before this happened,thank you!