we have had a summer home for 20 years that has a well with a plastic casing. The water has just become cloudy and has caused problems with screens on washing machines. It will clear if it is run for a considerable time...but every weekend now it is cloudy. How far from the bottom of the well should the pump be located. Is adding a whole house filter the best advise.. or what else can we do. The water was tested in the past and was 100% OK. the water has tasked great also.